BOOK     192.  1  1.H652    c.  1 

HOBBES    #    METAPHYSICAL    SYSTEM    OF 

THOMAS    HOBBES 


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i  a 


8 

THE  J^       \^> 

Metaphysical  System  of  Hobbes 

IN 

Twelve  Chapters  From 

ELEMENTS  OF  PHILOSOPHY  CON- 
CERNING BODY 

Together  With  Briefer  Extracts  From 

HUMAN  NATURE  and  LEVIATHAN 


SELECTED  BY 
MARY  WHITON  CALKINS 


u  The  world  ( I  mean  .  .  the  whole  mass  of  all  things 
that  are ),  is  corporeal,  that  is  to  say,  body;  .  .  and  that 
which  is  not  body  is  no  part  of  the  universe." 


SECOND    EDITION 

CHICAGO 
THE  OPEN  COURT  PUBLISHING  COMPANY 

1913 


Copyright  1905 

BY 

THE  OPEN  COURT  PUBLISHING  CO, 
Chicago 


PREFACE. 

This  condensation  of  the  English  version  of  Hobbes's 
book  Concerning  Body  has  been  made,  because  the 
work  is  the  completest  summary  of  the  metaphysical 
teaching  of  Hobbes  and  because  there  exists  no  inex- 
pensive reprint  or  compendium  of  it.  The  ethical  and 
social  doctrines  of  Hobbes  may  be  readily  studied  at 
first  hand,  by  the  aid  of  modern  editions  of  the  Le- 
viathan or  of  volumes  of  selections  from  the  writings 
of  Hobbes;  but  for  his  strictly  metaphysical  teaching 
one  must  now  have  recourse  to  the  volumes  of  the 
Molesworth  edition.  Teachers  of  modern  philosophy 
who  believe,  with  the  writer,  that  the  study  of  original 
texts  is  of  incomparable  value  to  the  student  must  have 
been  puzzled  in  their  efforts  to  be  just  to  the  claims  of 
materialism.  Convenient  expositions  of  idealism  are 
readily  found  in  the  editions  of  Berkeley's  Principles 
and  Dialogues.  But  no  historically  important  sum- 
mary of  materialistic  doctrine  has,  so  far,  been  accessi- 
ble. This  volume  aims  to  supply  the  need  and  also  to 
give  an  adequate  impression  of  the  Elements  of  Phi- 
losophy Concerning  Body.  To  gain  the  latter  end, 
chapters  have  been  included  from  all  four  Parts  of  the 
work,  and  the  headings  of  omitted  chapters  have  been 
printed  in  full.  To  represent  adequately  the  doctrine 
of  Hobbes,  it  has  been  necessary  to  add  to  the  formula- 
tion of  materialism,  as  contained  in  the  Concerning 
Body,    (i)    the  argument   for   materialism,   from  the 

iii 


iv  PREFACE. 

alleged  unreality  of  consciousness,  as  it  appears  in 
chapter  II.  of  Human  Nature;  and  (2)  the  corollary 
from  materialism,  the  teaching  that  spirit  is  a  form  of 
body,  from  the  later  chapters  of  Leviathan. 

The  only  portions  of  this  volume  which  duplicate 
recent  reprints  from  Hobbes  are  chapters  1,  6,  25,  and 
a  few  scattered  passages  from  Concerning  Body,  chap- 
ter 2  of  Human  Nature,  and  the  brief  selections  from 
Leviathan.  The  text  is  that  of  Molesworth  who, 
save  in  the  case  of  capitals  and  of  spelling,  follows  the 
early  editions.  Four  obvious  misprints,  including 
two  misplaced  Greek  accents,  have  been  changed. 

The  extracts  from  the  Latin  work  De  Corpore,  of 
which  Concerning  Body  is  a  version,  are  offered  in  rec- 
ognition of  the  fact  that  Hobbes  himself  did  not  make 
the  translation,  and  that  the  English  version,  spite  of  his 
revision,  has  not  the  authority  of  an  original  work.  It 
is  a  pity  not  to  reprint  the  Latin  original,  in  place  of 
the  English  version ;  but,  unhappily,  young  American 
students  either  are  not,  or  think  that  they  are  not, 
able  to  read  Latin  philosophical  texts.  By  way  of  a 
slight  protest  against  this  form  of  academic  illiteracy, 
no  life  of  Hobbes  is  here  printed  save  the  autobiog- 
raphy, in  Latin  verse,  written  at  the  age  of  eighty-four 
by  the  vigorous  old  philosopher.  Biographical  and 
historical  discussions  will  be  found  in  the  works  by 
Robertson,  Stephen  and  Sneath,  quoted  on  page  xxv., 
in  the  Bibliographical  Note.  For  an  exposition  of 
the  philosophy  of  Hobbes,  all  readers  are  referred  to 
Hobbes  himself. 

M.  W.  C. 


CONTENTS 

T.     Hobbes     Malmesburiensis     Vita vii 

Topical   List   of   the   Writings    of   Hobbes     ....     xviii 
Bibliographical    Note xxv 

Elements  of  Philosophy  Concerning  Body. 

Title    Page I 

Translator's    Preface 2 

The  Author's  Epistle  to  the  Reader 3 

PART    FIRST    OR    LOGIC. 

Chap.  I.— Of  Philosophy 5 

*Chap.  II. — Of  Names 15 

*Chap.  III.— Of    Proposition 16 

*Chap.  IV.— Of    Syllogism 16 

*Chap.  V. — Of  Erring,   Falsity,   and    Captions     ...  17 

Chap.  VI.— Of  Method 17 

PART   SECOND,  OR  THE  FIRST  GROUNDS   OF  PHILOSOPHY. 

Chap.  VII.— Of  Place  and  Time 43 

Chap.  VIII.— Of    Body    and    Accident 52 

Chap.  IX.— Of  Cause  and  Effect 69 

Chap.  X.— Of  Power  and  Act 76 

Chap.  XI. — Of  Identity  and  Difference 80 

Chap.  XII.— Of  Quantity 86 

*Chap.  XIIL— Of  Analogism,  or  the   Same   Proportion  92 
*Chap.  XIV.— Of     Strait     and     Crooked,     Angle     and 

Figure 92 

PART    THIRD,    OF    THE    PROPORTIONS    OF    MOTIONS    AND 
MAGNITUDES. 

Chap.  XV.— Of    the    Nature,    Properties,    and    Divers 

Considerations    of    Motion    and    Endeavour      .     .  95 


*Only    the    heading    of    this    chapter    is    reproduced. 

V 


vi  CONTENTS 

*Chap.  XVI. — Of    Motion    Accelerated    and    Uniform, 

and    of    Motion    by    Concourse 106 

*Chap.  XVII. — Of    Figures    Deficient 106 

*Chap.  XVIII.— Of  the  Equation  of  Strait  Lines  with 
the   Crooked   Lines   of   Parabolas   and  other   Fig- 
ures made  in  imitation  of  Parabolas     ....     107 
*Chap.  XIX.— Of  Angles   of  Incidence  and  Reflection, 

equal    by    Supposition 108 

*Chap.  XX.— Of  the  Dimension  of  a  Circle,  and  the  Di- 
vision of  Angles   or  Arches 109 

*Chap.  XXL— Of  Circular  Motion 109 

*Chap.  XXII.— Of  other  Variety  of  Motion     ....     no 
*Chap.  XXIIL— Of   the   Centre  of   Equiponderation   of 

Bodies  pressing  downwards  in  Strait  Parallel  Lines     in 
*Chap.  XXIV.— Of     Refraction     and     Reflection     .      .112 

PART    FOURTH,    OR    THE    PHENOMENA    OF    NATURE. 

Chap.  XXV. — Of  Sense  and  Animal  Motion     .      .      .  113 

*Chap.  XXVI.— Of  the  World  and  of  the  Stars     .     .  134 

Chap.  XXVII.— Of  Light,  Heat,  and  of  Colours     .      .  134 
*Chap.  XXVIII.— Of  Cold,  Wind,  Hard,  Ice,  Restitu- 
tion  of   Bodies   bent,   Diaphanous,   Lightning  and 

Thunder,  and  of  the  Heads  of  Rivers     ....  140 

Chap.  XXIX. — Of  Sound,  Odour,  Savour,  and  Touch  141 

Chap.  XXX.— Of  Gravity 153 

The  Doctrine  of  Hobbes  Concerning  the  Unreality 
of  Consciousness. 
Human  Nature—  Chap.  II 157 

The  Doctrine  of  Hobbes  Concerning  the  Na- 
ture of  Spirit  and  of  God. 

Leviathan,   Chap.   XL    (in   part) 165 

Chap.  XII 166 

Chap.  XXXI.    (in  part) 171 

Chap.    XXXIV.     (in    part) 173 

Selected  Passages  from  De  Corpore. 
183 


'Only    the    heading    of   this   chapter    is    reproduced. 


T.   HOBBES 

MALMESB  URIENSIS 

VJTA, 

SCRIPT  A  ANNO  MDCLXXII. 

Birth  Natus  erat  noster  servator  Homo-Deus  annos 

Mille  et  quingentos,  octo  quoque  undecies. 
Stabat  et  Hispanis  in  portubus  inclyta  classis 

Hostilis,  nostro  mox  peritura  mari : 
Primo  vere ;  dies  et  quintus  inibat  Aprilis : 

Illo  vermiculus  tempore  nascor  ego, 
Birthplace        in  Malmesburia ;  baptisma  a  patre  ministro 

Accepi,  et  nomen  mi  dedit  ille  suum. 
Oppidulum  parvum  est,  habuit  sed  multa  relatu 

Digna,  atque  imprimis  ccenobium  celebre, 
Et  castrum,  melius  nisi  sint  duo  castra  vocanda, 

Colle  sita,  et  bino  flumine  cincta  fere. 
Concilium  regni  binis  burgensibus  auget; 

Nunc  quoque  priscus  honor  permanet  ille  loci. 
Hie  et  Athelstani  conduntur  nobilis  ossa, 

Atque  super  tumulum  saxeus  ipse  jacet. 
Praemia  virtutis  populo  dedit  ille,  propinquos 

Sanguine  Danorum  qui  madefecit  agros : 
Study  Hue  et  ab  Aldhelmo  deducta  est  musa  Latina, 

Hie  habuit  primam  lingua  Latina  scholam. 
Non  est  ut  patriae  pudeat ;  sed  tempus  iniquum 

Conqueror,  et  mecum  tot  quoque  nata  mala. 
Fama  ferebat  enim  diffusa  per  oppida  nostra, 

Extremum  genti  classe  venire  diem. 
Atque  metum  tantum  concepit  tunc  mea  mater, 

Ut  pareret  geminos,  meque  metumque  simul. 
Hinc  est,  ut  credo,  patrios  quod  abominor  hos- 
tes, 

Pacem  amo  cum  musis,  et  faciles  socios. 
Disco  loqui  quatuor,  totidem  legere,  et  nume- 
rare, 

Non  bene  praeterea  fingere  literulas. 


Vlll 


VITA  THO.  HOBBES. 


Oxford 


Service  of 
Duke  of 
Devonshire 


Sex  annis  ad  verba  stcti  Graecae  atquc  Latinae, 

Et  decimo  quarto  mittor  ad  Oxonium. 
Hue  Magdalenae  veniens  admittor  in  aulam, 

Inque  ima  logicae  classe  locatus  eram. 
Et  praelectori  cum  primis  sedulus  adsum ; 

Is  licet  imberbis  cum  gravitate  legit, 
Barbara,  eelarent,  darii,  fcrio,  baralypton, 

Hos,  dicebat,  habet  prima  figura  modos. 
Cccsare,  camestres,  festino,  baroco,  darapti, 

Hsec  etiam  totidem  stat  variata  modis. 
Felapton,  disamis,  datisi,  bocardo,  ferison, 

Sunt  rursus  totidem  legitimique  modi. 
Quos  tarde  disco,  disco  tamen,  abjicioque, 

Admittorque  meo  quseque  probare  modo. 
Admoveor  physicae,  conflataque  cuncta  magister 

Materia  et  forma,  ut  partibus,  esse  docet; 
Et  species  rerum,  volitando  per  sera,  formas 

Donare  hinc  oculis,  auribus  inde  sonos. 
Multos  effectus  tribuit  syn  et  antipathic?, 

Et  supra  captum  talia  multa  meum. 
Ergo  ad  amcena  magis  me  verto,  librosque  re- 
volvo, 

Queis  prius  instructus,  non  bene  doctus  eram. 
Pascebamque   animum   chartis  imitantibus  or- 
bem, 

Telluris  faciem,  et  sydera  picta  videns : 
Gaudebam  soli  comes  ire,  et  cernere  cunctis 

Terricolis  ustos  qua  facit  arte  dies. 
Quoque  Dracus  filo  Neptunum,  Candisiusque 

Cinxerunt  medium ;  quaeque  adiere  loca  ■ 
Atque  hominum   exiguos,  si  possem,  cernere 
nidos, 

Et  picta  ignotis  monstra  videre  locis. 
Tempore  sed  justo  cum  Baccalaureus  Artis 

Essem   (namque  hie  est  primus  in  arte  gra- 
dus) 
Oxonium  linquo,  servitum  me  fero  in  amplam 

Gentis  Candisiae  conspicuamque  domum ; 
Rectorisque  aulae  commendat  Epistola  nostrae: 

Accipior,  placita  conditione  steti: 


VITA  THO.  HOBBES. 


Study  of 
classics 


Travel 


Atque  adolescenti  mox  applicor  ipse  adolscens : 

Tunc  patris  imperio  subditus  ille  fuit. 
Huic  ego  servivi  bis  denos  gnaviter  annos ; 

Non  Dominus  tantum,  verum  et  amicus  erat. 
Pars  erat  ilia  meae  multo  dulcissima  vitse, 

Et  nunc  saepe  mihi  somnia  grata  facit. 
Ille  per  hoc  tempus  mihi  praebuit  otia,  libros 

Omnimodos  studiis  praebuit  ille  meis. 
Vertor  ego  ad  nostras,  ad  Graecas,  atque  Latinas 

Historias ;  etiam  carmina  saepe  lego. 
Flaccus,  Virgilius,  fuit  et  mihi  notus  Homerus, 

Euripides,  Sophocles,  Plautus,  Aristophanes, 
Pluresque;  et  multi  Scriptores  Historiarum : 

Sed  mihi  prae  reliquis  Thucydides  placuit. 
Is  Democratia  ostendit  mihi  quam  sit  inepta, 

Et  quantum  ccetu  plus  sapit  unus  homo. 
Hunc  ego  scriptorem  verti,  qui  diceret  Anglis, 

Consultaturi  rhetoras  ut  fugerent. 
Urbes  externas  eadem  per  tempora  vidi, 

Germanas,  Francas,  Ausoniasque  adii. 
Mox  Dominum  morbo  devictum  vita  reliquit, 

Extremo  (ut  credas)  sed  reditura  die. 
Ante  tamen  fecit  mihi  ne  servire  necesse 

Esset,  qui  modice  vivere  suetus  eram. 
Deinde  domo  placita  nimium  neglectus  abivi, 

Parisiisque  moror  mensibus  octodecim. 
Inde  mei  Domini  revocor  praeceptor  ut  essem 

Nato ;  Devoniae  tunc  Comes  ille  fuit. 
Hunc  Romanarum  sensus  cognoscere  vocum ; 

Jungere  quoque  decet  verba  Latina  modo ; 
Fallere  quaque  solent  indoctos  rhetores  arte ; 

Quid  facit  orator,  quidque  poeta  facit; 
Et  demonstrandi  docui  praecepta,  globique 

Mundani   faciem,  multiplicesque  gyros. 
Litibus  et  finem,  faciunt  quas  plus,  minus,  et 
par, 

Qua  posset  usta  ponere  lege  dedi. 
Haes  ilium  docui  per  septem  sedulos  annos; 

Ille  celer  didicit,  retinuitque  memor. 


VITA  THO.  IiOBBES. 


Second 
journey 


Study  of 
physics 


Study  of 
philosophy 
and 
psychology 


Nee   tamcn   hoc    tempus   libris   consumpsimus 
omne, 

Ni  mundum  libri  dixeris  esse  loco. 
Italiae  multas,  Gallorum  et  vidimus  urbes ; 

Secessus  dulces  vidimus  Allobrogum. 
Ast  ego  perpetuo  naturam  cogito  rerum, 
Seu  rate,  seu  curru,  sive  ferebar  equo. 
Et  mihi  visa  quidem  est  toto  res  unica  mundo 

Vera,  licet  multis  falsificata  modis : 
Unica  vera  quidem,  sed  quae  sit  basis  earum 

Rerum,  quas  falso  dicimus  esse  aliquid ; 
Qualia  somnus  habet  fugitiva,  et  qualia  vitris 

Arbitrio  possum  multiplicare  meo ; 
Phantasiae,  nostri  soboles  cerebri,  nihil  extra; 

Partibus  internis  nil  nisi  mottts  inest. 
Hinc  est  quod,  physicam  quisquis  vult  discere, 
motus 

Quid  possit,  debet  perdidicisse  prius. 
Ergo  materiae  motusque  arcana  reculudo  ; 

Sic  tempus  vacuum  fallo  per  Italiam. 
Scribo  nihil,  facio  adversaria  nulla,  magistra 

Quae  docuit,  praesens  nam  mihi  semper  erat. 
Linquimus  Italiam,  rursusque  redimus  ad  alta 

Moenia  Lutetiae,  tectaque  magnifica. 
Hie  ego  Mersennum  novi,  communico  et  ill i 

De  rerum  motu  quae  meditatus  eram. 
Is  probat,   et   multis  commendat;  tempore  ab 
illo 

Inter  philosophos  et  numerabar  ego. 
In  patriam  rursus  post  menses  octo  reversus, 

De  conectendis  cogito  notitiis. 
Motibus  a  variis  feror  ad  rerum  variarum 

Dissimiles  species,  materiaeque  dolos ; 
Motusque   internos   hominum,   cordisque   late- 
bras; 

Denique  ad  imperii  justitiaeque  bona. 
His  ego  me  mersi  studiis.    Nam  philosophandi 

Corpus,  Homo,  Civis  continet  omne  genus. 
Tres  super  his  rebus  statuo  conscribere  libros ; 


VITA  THO.  I10BBES. 

Materiemque  mihi  congero  quoque  die. 
Nascitur  interea  scelus  execrabile  belli, 

Et  veniunt  studiis  tempora  iniqua  meis. 
Sexcentesimus  et  jam  quadragesimus  annus 

Post  millesimum  erat  virginis  a  puero, 
Cum  patriam  invasit  morbus  mirabilis,  unde 

Innumeri  e  doctis  post  periere  viri. 
Quo  quicunque  fuit  tactus,  divina  putabat 

Atque  humana  uni  cognita  jura  sibi. 
Jamque    in    procinctu    bellum    stetit.     Horreo 
spectans ; 

Meque  ad  dilectam  confero  Lutetiam. 
De  Cive  Postque  duos  annos  edo  De  Cive  libellum, 

Qui  placuit  doctis,  et  novus  omnis  erat ; 
Versus  et  in  varias  linguas  cum  laude  legebar, 

Gentibus  et  late  nomine  notus  eram. 
Laudabat  mediis  in  Erynnibus  Anglia,  et  illi 

Quorum  consiliis  cognitus  hostis  eram 
Sed  quod  consiliis  prcesentibus  utile  non  est, 

Ouantumvis  justum,  quis  put  at  esse  bonumf 
De  Corpore      Inde  annis  quatuor  libri  De  Corpore  forman, 

Qua  sit  scribendus,  nocte  dieque  puto. 
Comparo  corporeas  moles ;  et  cogito  rerum 

Visarum  formas  quid  variare  potest. 
Qusero  quibus  possim  rationis  Protea  vinclis 

Stringere,  fassurum  qua  tegit  arte  dolos. 
Adfuit  e  Minimis  Mersennus,  fidus  amicus; 

Vir  doctus,  sapiens,  eximieque  bonus. 
Cujus  cella  scholis  erat  omnibus  anterferenda ; 

Professorum  omnes  ambitione  tument. 
Illi  portabat,  si  dignum  forte  porisma 

Reppererat  quisquam,  principiumve  novum. 
Perspicuo  et  proprio  sermone,  carente  figuris 

Rhetoricis,  gnomis,  ambitione,  dolo, 
Ille  dedit  doctis,  qui  vellent,  rursus  ut  illud 

Vel  statim  possent,  vel  trutinare  domi. 
Edidit  e  multisque  inventis  optima  quaeque ; 

Signans  authoris  nomine  quidque  sui. 
Circa  Mersennum  convertebatur  ut  axem 

Unumquodque  artis  sidus  in  orbe  suo. 


xii  VITA  THO.  HOBBES. 

Ssevierat  bellum  quatuor  civile  per  annos, 
Anglos,  Hibernos  triverat  atque  Scotos. 
Perfidaque  in  castris  mansit  Fortuna  scelestis : 

Diffugere  via  qua  potuere  probi. 
Ipse  haeres  regni  Carolus,  comitante  caterva 

Armis  clarorum  et  nobilitate  virum, 
Lutetiam  venit,  expectans  dum  tempora  iniqua 

Transirent,  populi  desineretque  furor. 
Tunc  ego  decreram  De  Corpore  scribere  librum, 

Cujus  materies  tota  parata  fuit. 
Sed  cogor  differre ;  pati  tot  tantaque  fccda 

Apponi  jussis  crimina,  nolo,  Dei. 
Divi.nas  statuo  quam  primum  absolvere  leges ; 

Idque  ago  paulatim,  sollicitusque  diu. 
Namque    mathematical    studiis    dum    Principi 
adessem, 
Non  potui  studiis  semper  adesse  meis. 
Dein  per  sex  menses  morbo  decumbo,  propin- 
quae 
Accinctus  morti ;  nee  fugio,  ilia  fugit. 
Leviathan         Perfeci  librum  patrio  sermone ;  ut  ab  Anglis 
Posset  saepe  meis,  utiliterque  legi : 
Londinoque  typis  celer  evolat  in  regiones 

Vicinas,  notus  nomine  Leviathan. 
Militat  ille  liber  nunc  regibus  omnibus,  et  qui 

Nomine  sub  quovis  regia  ura  tenent. 
Interea  regem  vendit  Scotus,  et  necat  Anglus ; 

Jus  regni  Carolus  jamque  Secundus  habet, 
Lutetian  residens.    Vim  regni  turba  rebellis 
Occupat,  et  populum  jam  sine  lege  regit, 
Et  nomen  (quamvis  pauci)  sibi  Parliamenti 

Sumens,  se  satiat  sanguine  nobilium  ; 
Dejiciunt  mitras,  nee  firmant  Presbyteratum ; 
Clerica  nil  illic  profuit  ambitio. 
Exile  Lutetiam  ad  regem  multus  venit  inde  scholans 

Expulsus  patria,  tristis.  egenus,  onus. 
Hue  fuit  usque  meis  studiis  pax,  multiplicata 

Dum  facerent  annos  octo  per  octo  meos ; 
Sed  meus  ille  liber,  simul  atque  scholaribus  illis 
Lectus  erat,  Jani  dissiluere  fores. 


VITA  THO.  HOBBES.  > 

Nam  Regi  accusor  falso,  quasi  facta  probarem 

Impia  Cromwelli,  jus  scelerique  darem. 
Creditur ;  adversis  in  partibus  esse  videbar ; 

Perpetuo  jubeor  Regis  abesse  domo. 
Tunc    venit    in    mentem    mihi    Dorislaus,*    et 
Ascham  ;* 

Tanquam  proscripto  terror  ubique  aderat. 
Nee  de  rege  queri  licuit.     Nam  tunc  adolescens 

Credidit  ille,  quibus  credidit  ante  pater. 
Return  In  patriam  redeo  tutelae  non  bene  certus, 

Sed  nullo  potui  tutior  esse  loco : 
Frigus  erat,  nix  alta,  senex  ego,  ventus  acer- 
bus; 

Vexat  equus  sternax  et  salebrosa  via. 
Londinum  veniens,  ne  clam  venisse  viderer, 

Concilio  Status  conciliandus  eram. 
Quo  facto,  statim  summa  cum  pace  recedo, 

Et  sic  me  studiis  applico,  ut  ante,  meis. 
Solum  regnabat  tunc  nomine  Parliamentum; 

Praesul  erat  nullus,  Presbyterusque  nihil. 
Omnia  miles  erat,  committier  omnia  et  uni 

Poscebat;  tacite  Cromwell  is  unus  erat. 
Regia  conanti  calamo  defendere  jura, 

Quis  vitio  vertat  regia  jura  petens? 
Scribere  cuique  fuit  libertas,  quod  sibi  visum 

Esset,  contento  vivere  more  loci. 
Leviathan  clerum  at  totum  mihi   fecerat  hos- 
tem; 

Hostis  Theologum  nidus  uterque  fuit. 
Nam  dum  Papalis  Regni  contrecto  tumorem, 

Hos,  licet  abscissos,  lsedere  visus  eram. 
Contra  Leviathan,  primo,  convicia  scribunt, 

Et  causa,  ut  tanto  plus  legeretur,  erant. 
Firmius  inde'  stetit,  spero  stabitque  per  omne 

^vum,  defensus  viribus  ipse  suis. 
Justitise  mensura,  atque  ambitionis  elenchus, 

Regum  arx,  pax  populo,  si  doceatur,  erit. 


*  Regicidae  infames;  quorum  hie  apud  Hispanos, 
apud    Foederatos    Belgas    a    Parliamentariis    legatus, 
regiis  confossi  perierunt. 


XIV 


VITA  THO.  HOBBES. 


Controversy 

on 

mathematics 


Six  lessons 


Problems 


Ante  duos  minima  praemisi  mole  libellos ; 

Sed  nee  inest  parvis  gratia  parva  libris. 
Hie*  docet  motus  animi  et  phantasmata  sensus, 

Nee  sanos  patitur  spectra  timer e  viros: 
Alterf  at  Imperii  sanctissima  jura  repandit, 

Quseque  rudes  populos  vincula  sacra  tenent. 
Tandem    etiam    absolvo    librum   De    Corpore, 
cuj  us 

Materies  simul  et  forma  geometrica  est. 
Tunc  venit  in  lucem,  tota  plaudente  caterva 

Algebristarum,  Wallisii  algebrica, 
Ilia  Geometrise  pestis,  quae  coeperat  ante 

Annos  plus  centum,  nunc  et  ubique  furit. 
Ars  fuerat  numeros  quaesitos  inveniendi, 

Quam   docuit   Cheber,   et   quam   Diophantus 
habet. 
Deinde  per  hanc  artem  solam  problemata  solvi 

Posse  geometriae  cuncta  Vieta  docet. 
Addidit  Oxoniae  Praelector  Savilianus 

Wallisius  multo  nobile  dogma  magis : 
Nempe  infinitae  molis  finem  esse,  et  habere 

Finitum  partes  et  sine  fine  datas : 
Quae  duo  fecerunt  insanos  dogmata,  quotquot 

Festinaverunt  esse  geometrici. 
Haec  mihi  causa  satis  scribendi  est  justa  libelli, 

(Annos  natus  eram  septuaginta  duos) 
In  quo,  Colloquiis  ego  Sex  non  molliter  istos 

Tango  geometras,  tit  meruere,  novos ; 
Sed  nil  profeci,  magnis  authoribus  error 

Fulttis  erat;  cessit  sic  medicina  malo. 
Tunc  quoque  scribo  duos  patrio  sermone  libellos 

Contra  Bramhallum.     Quaestio  sola  fuit, 
Cujus  ad  arbitrium  volumns,  nostrnmne,  Deine: 

Ille  scholam  sequitur,  sed  mihi  dux  ratio  est. 
Sex    quoque    post    paulo    scripsi    Problemata, 
librum 

Exiguum,  at  purae  fonticulum  physicae. 


*  Liber  de  Natura  Humana. 
f  Lib.  de  Corpore  Politico. 


VITA  THO.  HOBBES. 

Nam  doceo  natnra  locis  qua  dejicit  arte 

Sublimes  lapides,  res  aliasque  graves ; 
Qua  situla  sol  haurit  aquas;  ut  frigora  ventus 

Efficit ;  et  venti  qua  ratione  volant : 
Quo  pendent  steriles,  volitantque  per  sera  nubes, 

Quo  fulcro  gravidas  destituente  ruunt ; 
Et  quo  consistunt  durorum  glutine  partes, 

Duraque  quae  rursus  mollia  causa  facit ; 
Unde  fragor  ccelo,  qua  nix  glaciesque  fit  arte ; 

Excussusque  altis  emicat  ignis  aquis ; 
Quid  res  exiguas  conjungit  in  aere  sparsas, 

Et  calidum  Phcebus  qua  ratione  facit ; 
Herculeusque     lapis     ferrum    quibus    attrahit 
uncis, 

Observatque  suae  matris  utrumque  polum ; 
Cur  mare  non  aequis  ad  littora  volvitur  undis ; 

Anno,  mense,  die  quoque,  bis  auget  aquas ; 
Et  quare,  vento  duce,  navis  it  obvia  vento  ; 

Haec  habet  et  monstrat  parvulus  ille  liber. 
Et  valitura  puto  cum  tempore;  quandoquidem 
nunc 

Inter  tot  Momos  irreprehensa  manent. 
JEris  et  parvo  naturam  scribo  libello 

Adversus  quandam  machinam  inanificam. 
Tunc  physicam  linquens,  ad  amata  mathemata 
vertor ; 

Namque  meo  tandem  cesserat  hostis  agro. 
Tantum  non  lapidem  potnissem  vera  docere, 

Clamosas  speret  nemo  docere  scholas. 
Ve  Principals   At  De  Principiis  alium  tamen  edo  libellum, 

Fecique  ut  posset  clarius  esse  nihil. 
In  quo  naturam  rationis  ita  explico,  ut  illam 

Nemo  non  claram  diceret  atque  probam. 
Hac  mihi  parte  fuit  victoria  cognita  cunctis, 

Dissimulant  aliis  vulnera  magna  locis ; 
Deficiunt  animis,  sed  deficientibus  insto, 

Culminaque  inscendo  summa  geometriae. 
Namque  parem  cyclum  quadrato  publico ;  nec- 
non 

Jactatum  Pythii  monstro  porisma  Dei; 


XVI 


VITA  THO.  HOBBES. 


Demonstrata  prius,  sed  non  rationibus  iisdem, 

Sperabam  methodo  vincere  posse  nova. 
Sed  nil  profeci,  densis  umbonibus  obstant, 

Cedere  quos  puduit,  semi-mathematici. 
Ergo  meam  statuo  non  ultra  perdere  opellam, 

Indocile  expectans  discere  posse  pecus. 
Rosetum,         Deinde  librum  scribo,  quern  nomine  dico  Rose- 
turn, 

Praecipuo  densum  flore  geometriae. 
Wallisius  contra  pugnat ;  victusque  videbar 

Algebristarum  Theologumque  scholis. 
Et  simul  eductus  castris  exercitus  omnis 

Pugnae  securus  Wallisianus  ovat ; 
Quem  cum  vidissem  salebroso  insistere  campo, 

Stabat  ubi  radix  densa,  molesta,  tenax, 
Pugna  placet,  vertor ;  numerum  licet  infinitum 

Temporis  in  puncto  dissipo,  sterno,  fugo. 
Bella  mea  audisti.     Quid  vis  tibi  dicier  ultra? 

An  quam  dives,  id  est,  quam  sapiens  fuerim? 
Anne  refert  quot  agros  habui,  quot  millia  num- 
mum? 

Si  percontator  forte  rogabit  et  hoc, 
Exiguus  mihi  fundus  erat  propriusque  relictus 

Quem  fratri  dono,  ductus  amore,  dedi. 
Parva  superficies,  sed  millia  multa  ferebat 

Granorum  tritici,  nam  bona  terra  fuit. 
Longa  satis  votis  regum;  et  nisi  tota  deorsum 

Tensa  foret,  Rex  nunc  magnus  haberer  ego. 
Ut  primum  belli  sensi  civilis  odorem, 

Et  populum  ventos  vidi  agitasse  levem : 
Quaero  locum  studiis,  et  vitae  commodiorem, 

Hinc  me  Parisios  transfero  remque  meam. 
Quingentae  mihi  erat  numerata  pecunia  librae, 

Cum  fugiens  patriae  littora  linquo  meae: 
Legacy  His  aliae  paulo  post  accessere  ducentae  * 

Et  simul  immensus  perpetuusque  dolor. 
(Godolphine  jaces;  purae  rationis  amator, 

Justitiae  et  Veri  miles  amande,  vale.) 


*  Ex  Legato  Sydn.  Godolphini. 


VITA  THO.  HOBBES.  x 

Venit  et  e  patria  mihi  pensio  certa  quotannis, 

Bis*  quadragintis  constitit  ilia  libris. 
Pension  from  Deinde  redux  mihi  Rex  concessit  habere  quo- 
King  tannis 

Centum  alias  libras  ipsius  ex  loculis, 
Dulce  mihi  donum.     Convicia  sperno  aliorum, 

Quando  teste  ipso  judicor  esse  probus. 
His  ego  contentus  vivo,  nee  prsefero  plura ; 

Quis  vellet  sanus  re  minor  esse  sua? 
Rem,    si    quando    lubet,    per    vestros    supputo 
Sousos, 

Ut  fiat  major:  si  neque  sic  satis  est, 
Per  Maravedisios  numero,  videorque  beatus 

Crcesos  et  Crassos  vincere  divitiis. 
Ipse  meos  nosti,  Verdusi  candide,  mores, 

Et  tecum  cuncti  qui  mea  scripta  legunt. 
Nam  mea  vita  meis  non  est  incongrua  scriptis : 

Justitiam  doceo,  justitiamque  colo. 
Improbus  esse  potest  nemo  qui  non  sit  avarus, 

Nee  pulchrum  quisquam  fecit  avarus  opus. 
Octoginta  ego  jam  complevi  et  quatuor  annos: 

Pene  acta  est  vitre  fabula  longa  meae. 


Ex    munere    Comitis    Devonian 


TOPICAL  LIST  OF  THE  WRITINGS  OF 
HOBBES. 


The  dates  and  the  Latin  titles  are  transferred 
from  the  catalogue  of  Ant.  a  Wood,  as  reprinted  in 
Molesworth's  edition  of  the  Opera  Latina  (cited  as 
Op.  Lat.),  Vol.  I.  The  English  titles  are  those  of 
Molesworth's  edition  of  the  English  works  (cited  as 
E.  W.),  except  when  these  conflict  with  the  titles 
quoted  by  Robertson  from  the  early  editions.  All 
works,  unless  otherwise  indicated,  were  published  in 
London. 

I.     Writings  on  Metaphysics. 


1641.  Objections    in    Cartesii    de    prima    Philosophia 
Meditationes. 

Published    in    all    the   early    editions    of    Descartes's 
Meditations,    Paris    and    Amsterdam. 

1655.  Elementa  Philosophise  Sectio  prima  de  Corpore, 

8vo,  1655.     Op.  Lat.  Vol.  I. 

1656.  Elements  of  Philosophy,  The  First  Section  Con- 

cerning Body.     E.  W.  I. 

A  translation,   not   by   Hobbes,   of  the  De  Corpore. 
Cf.    pp.   ii.   and    183    of   this   volume. 

See,  also,  for  metaphysical  discussion,  Leviathan  (esp. 
chapters  12,  31,  34)  ;  the  ethical  writings;  An  Answer 
to  a  Book    ...    by  Dr.  Bramhall. 

II.    Writings  on  Mathematics  and  Physics. 


1644.  Tractatus  Opticus.     Op.  Lat.  V. 

Published  by  IV: 
Physico-Matl 

1655.  De  Corpore. 


Published  by  Mersenne,    in    1644,    in    his    Cogitata 
Physic o-Mathematica. 


XV111 


THE  WRITINGS  OF  HOBBES.  xix 

1656.  Concerning  Body. 

These  two  works,  already  quoted  by  their  full  titles, 
contain  the  mathematical  as  well  as  the  meta- 
physical doctrine  of  Hobbes.  This  follows  nat- 
urally from  his  conviction,  that  "  every  part  of 
the  universe  is  body,"  for,  if  this  be  granted,  the 
mathematical  laws  of  the  physical  world  are  the 
principles  of  all  reality.  Hobbes,  however,  de- 
spite his  pretensions,  was  never  other  than  an 
amateur  in  mathematics;  and  the  mathematical 
chapters  of  De  Corpore,  along  with  much  irrele- 
vant matter,  contain  one  colossal  blunder:  the  at- 
tempt (C.  XX.)  at  squaring  the  circle.  The  error 
was  exposed  at  once  by  Wallis,  Savilian  professor 
of  geometry  at  Oxford,  in  his  Elenchus  Geomet- 
ric Hobbiance.  This  work  was  the  starting-point 
of  a  bitter  controversy,  lasting  more  than  twenty 
years.  So  far  as  the  mathematical  issues  were 
concerned,  Hobbes  was  always  in  the  wrong;  but 
he  never  acknowledged  defeat,  and  returned  with 
courage  worthy  of  a  better  cause,  again  and  again 
to  the  unequal  struggle.  (Cf.  esp.  Robertson's 
"  Hobbes,"  pp.  167  seq.)  It  should,  however,  be 
noted  that  he  modified  the  mathematical  chapters, 
both  in  the  later  editions  of  De  Corpore  (followed 
in  Molesworth's  Op.  Lat.,  which  are  based  on  the 
collected  edition  of  1668)  and  also  in  the  English 
version,  Concerning  Body.  All  the  titles  in  this 
section  are  of  works  concerned  in  this  discussion. 
Unless  otherwise  described,  all  are  to  be  found 
either  in   Op.  Lat.  IV.   or  in  E.    W.    VII. 

1656.  Six  Lessons  to  the  Professors   of  the  Mathe- 

matics, ...  in  the  Chairs  set  up  by 
.  .  .  Sir  Henry  Savile  in  the  University 
of  Oxford. 

1657.  2TIFMAI  or   Marks  of  the  Absurd  Geometry, 

Rural  Language,  Scottish  Church  Politics  and 
Barbarisms  of  John  Wallis. 

1660.  Examinatio  et  Emendatio  Mathematical  Hodier- 

nge. 

1661.  Dialogus  Physicus,  sive  de  Natura  ^ris. 


xx  THE  WRITINGS  OF  HOBBES. 

1661.  De  Duplicatione  Cubi,  Paris. 

Molesworth  docs  not  print  this  in  the  original 
French,  but  only  in  the  modified  English  form, 
as  the  concluding  pages  of  the  Dialogus  Physicus. 

1662.  Problemata  Physica,  una  cum  Magnitudine  Cir- 

culi. 
1666.  De  Principiis  et  Ratiocinatione  Geometrarum. 
1669.  Quadratura    Circuli,    Cubatio    Sphaerae,    Dupli- 

catio  Cubi;  una  cum  Responsione  ad  Objec- 

tiones  Geometriae  Professoris  Saviliani. 
1671.  Rosetum    Geometricum,     .     .     .     cum    Censura 

brevi    Doctrinae    Wallisianae    de    Motu.     Op. 

Lat  V. 

1 67 1.  Three   Papers   Presented  to  the  Royal  Society 

against  Dr.  Wallis. 

1672.  Lux  Mathematica.     Op.  Lat.  V. 

1672.  Principia  et  Problemata  aliquot  geometrica  ante 
desperata     .     .     .     Op.  Lat.  V. 

1678.  Decameron  Physiologicum,  or  Ten  Dialogues  of 
Natural  Philosophy. 

(posthumous  works.) 

1682.  Seven  Philosophical  Problems  and  Two  Propo- 
sitions of  Geometry. 

A  shortened  translation  of  Problemata  Physica, 
1662. 

III.    Writings  on  Psychology. 
1650.  Human  Nature.     E.  W.  IV. 

The  logical  foundation  both  of  Hobbes's  metaphysics 
and  of  his  political  philosophy.  Actually  the  first 
of  his  systematic  works,  written  in  1640  and  at 
that  time  combined  with  the  De  Corpore  Politico, 
under  the  title,  The  Elements  of  Law,  Natural  and 
Politique.  (Cf.  Robertson,  "  Hobbes,"  p.  51  and 
p.   67,   Note.) 


THE  WRITINGS  OF  HOBBES.  xxi 

1657.  De  Homine,  sive  Elementorum  Philosophise 
Sectio  Secunda.     Op.  Lat.  II. 

An  ill  proportioned  work,  less  complete  than  Human 
Nature  and  containing  many,  chiefly  irrelevant, 
chapters  on  optics. 

See  also,  for  psychological  discussion:  Leviathan,  Pt. 
I. ;  De  Corpore,  Pt.  IV. ;  Concerning  Body,  Pt.  IV. ; 
Decameron  Physiologicum. 

IV.     Writings  on   "  Civil  Philosophy    (or   Poli- 
tics)." 

1642.  Elementorum  Philosophise  Sectio  Tertia  De 
Cive.     Paris. 

Privately  printed.  Re-printed,  in  1647,  with  altered 
title,  thus: 

1647.  Elementa  Philosophica  de  Cive.  Amsterdam. 
Op.  Lat.  II. 

1 65 1.  Philosophical  Rudiments  concerning  Govern- 
ment and  Society.     E.  W .  II. 

1650.  De  Corpore  Politico,  or  the  Elements  of  Law, 

Moral  and  Politic.     E.  W.  IV. 

Written  in  1640  (Cf.  Note,  above,  on  Human  Na- 
ture.) As  compared  with  the  De  Cive,  this  work 
lays  less  emphasis  on  the  power  of  the  state  in 
ecclesiastical  matters. 

165 1.  Leviathan:  Or,  the  Matter,  Form  and  Power  of 

a    Commonwealth,    Ecclesiastical    and    Civil. 
E.  IV.  III. 

The  most  popular,  forcible  and  detailed  discussion  of 
the  political  theory  of  Hobbes,  prefixed  by  several 
chapters   on   psychology. 

1668.  Leviathan.     Amsterdam.     Op.  Lat.  III. 

A  translation,  by  Hobbes  himself,  into  Latin.  The 
Latin  version  omits  and  alters  certain  portions  of 
the  English  original.     It  included: 


jtxii  THE  WRITINGS  OF  HOBBES. 

1668.  Appendix  ad  Leviathan.  Amsterdam.  Op. 
Lat.  III. 

The  Appendix  sets  forth  (1)  that  the  teaching  of 
Leviathan  is  not  heretical  and  (2)  that  there  re- 
mains in  England  no  court  of  heresy. 

(POSTHUMOUS    WORKS.) 

For  the  following  works,  Hobbes  did  not  succeed  in 
obtaining    the    censor's    license:  — 

1680.  Behemoth :  The  History  of  the  Causes  of  the 
Civil  Wars  of  England  .  .  .  from  the  Year 
1640  to  the  Year  1660.     E.  W.  VI. 

Written  about  1668.  Several  unauthorized  and  in- 
accurate editions  appeared  before  1680. 

1680.  An  Historical  Narration  concerning  Heresy  and 

the     Punishment     Thereof.     (London?)     E. 
W.  IV. 

Written  about  1666,  after  the  abortive  parliamentary 
proceedings  against  Leviathan. 

1 68 1.  A  Dialogue  between  a  Philosopher  and  a  Student 

of  the  Common  Laws  of  England.     E.  W.  VI. 

Written   about    1666. 

1682.  An  Answer  to  a  Book  Published  by  Dr.  Bram- 

hall     .      .      .     called    Catching    of    the    Le- 
viathan.    E.  W.  IV. 

Written  in  1668.  A  refutation  of  Bramhall's  charge, 
"  that  the  Hobbian  principles  are  destructive  to 
Christianity  and  to  all  religion." 

1688.  Historia  Ecclesiastica  Romana,  Poema  .  r  .  . 
ubi  de  Superstitionis  Origine,  progressu,  &c. 
Op.  Lat.  V. 

Written,  about  1670.  An  English  version  was  pub 
lished  in    1722. 


THE  WRITINGS  OF  HOBBES.  xxiii 

V.     Writings  on  Ethics. 
1654.  Of  Liberty  and  Necessity.     E.  IV.  IV. 

Written  in  in  1646,  as  part  of  a  private  discussion 
with  Bishop  Bramhall;  published  without  the  con- 
sent of  Hobbes.  (Cf.  Robertson,  "  Hobbes,"  p. 
163  seq.) 

1656.  The    Questions    concerning    Liberty,    Necessity 
and  Chance,  Clearly  Stated  and  Debated  be- 
tween Dr.   Bramhall,  Bishop  of   Derry,  and 
Thomas  Hobbes,  of  Malmesbury.     E.  W .  V. 
See,  also,  Writings  on  Civil  Philosophy. 

VI.    Writings  on  Rhetoric  and  on  Miscellaneous 

Subjects. 

1636.  De  Mirabilibus  Pecci  liber. 

Account  of  an  excursion  round  Derbyshire  Peak. 
Written   before    1628,   Op.   Lat.    V. 

1650.  The   Answer  of   Mr.    Hobbes   to   Sir   William 
Davenant's  Preface  before  Gondibert. 

A  letter  on  the  nature  of  poetry,  apropos  of  the  poet 
laureate's   heroic   poem,   Gondibert,   E.    W.  IV. 

1669.  Letter  to  the  Right  Honorable  Edw.  Howard. 

Published  as  prefix  to  Mr.  Howard's  poem,  The 
British    Princes. 

(POSTHUMOUS    WORKS.) 

1681.  The  Whole  Art  of  Rhetoric.     E.  IV.  VI. 

An  English  abstract  oi  that  Latin  version  of  Aris- 
totle's Rhetoric,  dictated  between  1630  and  1640, 
by  Hobbes,  to  his  pupil,  the  young  Earl  of  Devon- 
shire. To  this  is  added,  in  the  edition  of  1681, 
short  treatises  on: 


xxiv  THE  WRITINGS  OF  HOBBES. 

The  Art  of  Rhetoric, 
The  Art  of  Sophistry. 

VII.    Translations. 

1628.  Eight  Books  of  the  Peloponnesian  War,  written 
by  Thucydides  .  .  .  Interpreted  with  Faith 
and  Diligence  immediately  out  of  the  Greek. 
E.  W.  VIII.  and  IX. 

1674.  Voyage  of  Ulysses. 

A  rhymed  translation  of  Odyssey,  Bks.  IX.-XII., 
later  incorporated  in  the  complete  translation: 

1675.  The  Iliads  and  Odysses  of  Homer.     Translated 

out  of  Greek  into  English.  With  a  large 
preface  concerning  the  Virtues  of  an  Heroic 
Poem.     E.  W.  X. 

VIII.     Personal  Writings. 

1662.  Considerations  upon  the  Reputation,  Loyalty, 
Manners  and  Religion  of  Thomas  Hobbes. 
E.  W.  IV.     ■ 

A  reply  to  the  personal  charges  of  Wallis's  Hobbius 
Heautontimorumenos. 

1674.  Epistola  ad  Antony  a  Wood.  (London?)  Not 
included  in  Op.  Lat. 

A  protest  against  Dean  Fell's  abuse  of  Hobbes  in 
the  translation  of  Wood's  History  and  Antiquities 
of  Oxford. 

i6yg.  Vita  Ejus  Latino  Carmine.     Op.  Lat.  I. 


THE  WRITINGS  OF  HOBBES.  xxv 

(posthumous  works.) 
1681.  T.  Hobbes  Malmesburiensis  Vita.     Op.  Lat.  I. 

A  prose  life,  attributed  to  Hobbes. 

See,  also,  for  personal  allusions,  all  the  controversial 
writings  of  Hobbes;  and  for  a  few  letters,  E.  W. 
VII.  and  Op.  Lat.  V. 


BIBLIOGRAPHICAL  NOTE. 

For  references  to  contemporary  criticism  of  Hobbes,  usually 
unsympathetic  and  often  violent,  see  R.  Blackbourne,  Vitae 
Hobbianse  Auctarium  (1681),  Op.  Lat.  I.,  p.  Ixix.  seq. 

For  references  to  works  of  exposition  and  of  criticism,  from 
the  later  seventeenth  century  onward,  see  Sneath,  "  The  Ethics 
of  Hobbes"  (1898),  Introduction,  p.  xii.  seq.;  Robertson,  (1) 
"Hobbes"  (1886),  chaps.  IX.  and  X.,  (2)  article  in  Encycl. 
Brit.,  9th  ed.,  vol.  XII.,  footnotes. 

The  most  useful  of  recent  works  on  the  life,  writing  and 
system  of  Hobbes  include  the  books,  just  mentioned,  of  Rob- 
ertson and  of  Sneath,  and  the  following:  "Hobbes"  (1904), 
by  Leslie  Stephen,  and  "Hobbes,  Leben  und  Lehre,"  (Stutt- 
gart, 1896)  by  F.  Tonnies,  and  Woodbridge,  "The  Philosophy 
of  Hobbes  in  Extracts  and  Notes  from  his  Writings"  (1903)- 


ELEMENTS  OF  PHILOSOPHY. 

THE  FIRST  SECTION, 

CONCERNING  BODY, 

WRITTEN  IN  LATIN 

BY 

THOMAS  HOBBES  OF  MALMESBURY, 

AND 

TRANSLATED  INTO  ENGLISH. 


THE 

TRANSLATOR  TO  THE  READER. 

If,  when  I  had  finished  my  translation  of  this  first  sec- 
tion of  the  Elements  of  Philosophy,  I  had  presently 
committed  the  same  to  the  press,  it  might  have  come  to 
your  hands  sooner  than  now  it  doth.  But  as  I  under- 
took it  with  much  diffidence  of  my  own  ability  to  per- 
form it  well ;  so  I  thought  fit,  before  I  published  it,  to 
pray  Mr.  Hobbes  to  view,  correct,  and  order  it  accord- 
ing to  his  own  mind  and  pleasure.  Wherefore,  though 
you  find  some  places  enlarged,  others  altered,  and  two 
chapters,  XIII  and  XX,  almost  wholly  changed,  you 
may  nevertheless  remain  assured,  that  as  now  I  present 
it  to  you,  it  doth  not  at  all  vary  from  the  author's  own 
sense  and  meaning.     ********** 


THE 

AUTHOR'S  EPISTLE  TO  THE  READER. 

Think  not,  Courteous  Reader,  that  the  philosophy, 
the  elements  whereof  I  am  going  to  set  in  order,  is 
that  which  makes  philosophers'  stones,  nor  that  which 
is  found  in  the  metaphysic  codes ;  but  that  it  is  the  nat- 
ural reason  of  man,  busily  flying  up  and  down  among 
the  creatures,  and  bringing  back  a  true  report  of  their 
order,  causes  and  effects.  Philosophy,  therefore,  the 
child  of  the  world  and  your  own  mind,  is  within  your- 
self;  perhaps  not  fashioned  yet,  but  like  the  world  its 
father,  as  it  was  in  the  beginning,  a  thing  confused. 
Do,  therefore,  as  the  statuaries  do,  who,  by  hewing  off 
that  which  is  superfluous,  do  not  make  but  find  the 
image.  Or  imitate  the  creation :  if  you  will  be  a  phi- 
losopher in  good  earnest,  let  your  reason  move  upon 
the  deep  of  your  own  cogitations  and  experience ;  those 
things  that  lie  in  confusion  must  be  set  asunder,  dis- 
tinguished, and  every  one  stamped  with  its  own  name 
set  in  order ;  that  is  to  say,  your  method  must  resemble 
that  of  the  creation.  The  order  of  the  creation  was, 
light,  distinction  of  day  and  night,  the  firmament,  the 
luminaries,  sensible  creatures,  man;  and,  after  the  crea- 
tion, the  commandment.  Therefore  the  order  of  con- 
templation will  be,  reason,  definition,  space,  the  stars, 
sensible  quality,  man;  and  after  man  is  grown  up,  sub- 
jection to  command.  In  the  first  part  of  this  section, 
which  is  entitled  Logic,  I  set  up  the  light  of  reason. 
In  the  second,  which  hath  for  title  the  Grounds  of 
3 


4  CONCERNING  BODY. 

Philosophy,  I  distinguish  the  most  common  notions  by 
accurate  definition,  for  the  avoiding  of  confusion  and 
obscurity.  The  third  part  concerns  the  expansion  of 
space,  that  is  Geometry.  The  fourth  contains  the  Mo- 
tion of  the  Stars,  together  with  the  doctrine  of  sensible 
qualities. 

In  the  second  section,  if  it  please  God,  shall  be  han- 
dled Man.  In  the  third  section,  the  doctrine  of  Sub- 
jection is  handled  already.  This  is  the  method  I  fol- 
lowed; and  if  it  like  you,  you  may  use  the  same;  for 
I  do  but  propound,  not  commend  to  you  anything  of 
mine.  But  whatsoever  shall  be  the  method  you  will 
like,  I  would  very  fain  commend  philosophy  to  you, 
that  is  to  say,  the  study  of  wisdom,  for  want  of  which 
we  have  all  suffered  much  damage  lately.  For  even 
they,  that  study  wealth,  do  it  out  of  love  to  wisdom; 
for  their  treasures  serve  them  but  for  a  looking-glass, 
wherein  to  behold  and  contemplate  their  own  wisdom. 
Nor  do  they,  that  love  to  be  employed  in  public  busi- 
ness, aim  at  anything  but  place  wherein  to  show  their 
wisdom.  Neither  do  voluptuous  men  neglect  philoso- 
phy, but  only  because  they  know  not  how  great  a  pleas- 
ure it  is  to  the  mind  of  man  to  be  ravished  in  the 
vigorous  and  perpetual  embraces  of  the  most  beauteous 
world.  Lastly,  though  for  nothing  else,  yet  because 
the  mind  of  man  is  no  less  impatient  of  empty  time 
than  nature  is  of  empty  place,  to  the  end  you  be  not 
forced  for  want  of  what  to  do,  to  be  troublesome  to 
men  that  have  business,  or  take  hurt  by  falling  into 
idle  company,  but  have  somewhat  of  your  own  where- 
with to  fill  up  your  time,  I  recommend  unto  you  to 
study  philosophy.     Farewell. 

T.  H. 


COMPUTATION  OR  LOGIC. 

CHAPTER  I. 

OF   PHILOSOPHY. 

i.  The  Introduction.— 2.  The  Definition  of  Philosophy  ex- 
plained.—3.  Ratiocination  of  the  Mind.— 4.  Properties,  what 
they  are. — 5.  How  Properties  are  known  by  Generation,  and 
contrarily.— 6.  The  Scope  of  Philosophy.— 7.  The  Utility  of 
it.— 8.  The  Subject.— 9.  The  Parts  of  it.— 10.  The  Epilogue. 

Philosophy  seems  to  me  to  be  amongst  men  now, 
in  the  same  manner  as  corn  and  wine  are  said  to  have 
been  in  the  world  in  ancient  time.  For  from  the  be- 
ginning there  were  vines  and  ears  of  corn  growing 
here  and  there  in  the  fields ;  but  no  care  was  taken  for 
the  planting  and  sowing  of  them.  Men  lived  there- 
fore upon  acorns ;  or  if  any  were  so  bold  as  to  venture 
upon  the  eating  of  those  unknown  and  doubtful  fruits, 
they  did  it  with  danger  of  their  health.  In  like  man- 
ner, every  man  brought  Philosophy,  that  is,  Natural 
Reason,  into  the  world  with  him;  for  all  men  can 
reason  to  some  degree,  and  concerning  some  things: 
but  where  there  is  need  of  a  long  series  of  reasons, 
there  most  men  wander  out  of  the  way,  and  fall  into 
error  for  want  of  method,  as  it  were  for  want  of  sow- 
ing and  planting,  that  is,  of  improving  their  reason. 
And  from  hence  it  comes  to  pass,  that  they  who  con- 
tent themselves  with  daily  experience,  which  may  be 

5 


6  CONCERNING  BODY. 

likened  to  feeding  upon  acorns,  and  either  reject,  or 
not  much  regard  philosophy,  are  commonly  esteemed, 
and  are,  indeed,  men  of  sounder  judgment  than  those 
who,  from  opinions,  though  not  vulgar,  yet  full  of 
uncertainty,  and  carelessly  received,  do  nothing  but 
dispute  and  wrangle,  like  men  that  are  not  well  in 
their  wits.  I  confess,  indeed,  that  that  part  of  philoso- 
phy by  which  magnitudes  and  figures  are  computed,  is 
highly  improved.  But  because  I  have  not  observed 
the  like  advancement  in  the  other  parts  of  it,  my  pur- 
pose is,  as  far  forth  as  I  am  able,  to  lay  open  the  few 
and  first  Elements  of  Philosophy  in  general,  as  so 
many  seeds  from  which  pure  and  true  Philosophy  may 
hereafter  spring  up  bye  little  and  little. 

I  am  not  ignorant  how  hard  a  thing  it  is  to  weed  out 
of  men's  minds  such  inveterate  opinions  as  have  taken 
root  there,  and  been  confirmed  in  them  by  the  author- 
ity of  most  eloquent  writers;  especially  seeing  true 
(that  is,  accurate)  Philosophy  professedly  rejects  not 
only  the  paint  and  false  colours  of  language,  but  even 
the  very  ornaments  and  graces  of  the  same;  and  the 
first  grounds  of  all  science  are  not  only  not  beautiful, 
but  poor,  arid,  and,  in  appearance,  deformed.  Never- 
theless, there  being  certainly  some  men,  though  but 
few,  who  are  delighted  with  truth  and  strength  of  rea- 
son in  all  things,  I  thought  I  might  do  well  to  take 
this  pains  for  the  sake  even  of  those  few.  I  proceed 
therefore  to  the  matter,  and  take  my  beginning  from 
the  very  definition  of  philosophy,  which  is  this. 

2.  Philosophy  is  such  knowledge  of  effects  or 
appearances,  as  we  acquire  by  true  ratiocination  from 
the  knowledge  we  have  -first  of  their  causes  or  genera- 
tion: And  again,  of  such  causes  or  generations  as  may 
be  from  knowing  -first  their  effects. 


OF  PHILOSOPHY.  7 

For  the  better  understanding  of  which  definition,  we 
must  consider,  first,  that  although  Sense  and  Memory 
of  things,  which  are  common  to  man  and  all  living 
creatures,  be  knowledge,  yet  because  they  are  given  us 
immediately  by  nature,  and  not  gotten  by  ratiocination, 
they  are  not  philosophy. 

Secondly,  seeing  Experience  is  nothing  but  memory ; 
and  Prudence,  or  prospect  into  the  future  time,  noth- 
ing but  expectation  of  such  things  as  we  have  already 
had  experience  of,  Prudence  also  is  not  to  be  esteemed 
philosophy. 

By  ratiocination,  I  mean  computation.  Now  to 
compute,  is  either  to  collect  the  sum  of  many  things 
that  are  added  together,  or  to  know  what  remains  when 
one  thing  is  taken  out  of  another.  Ratiocination, 
therefore,  is  the  same  with  addition  and  substraction; 
and  if  any  man  add  multiplication  and  division,  I  will 
not  be  against  it,  seeing  multiplication  is  nothing  but 
addition  of  equals  one  to  another,  and  division  nothing 
but  a  substraction  of  equals  one  from  another,  as  often 
as  is  possible.  So  that  all  ratiocination  is  compre- 
hended in  these  two  operations  of  the  mind,  addition 
and  substraction. 

3.  But  how  by  the  ratiocination  of  our  mind,  we 
add  and  substract  in  our  silent  thoughts,  without  the 
use  of  words,  it  will  be  necessary  for  me  to  make  in- 
telligible by  an  example  or  two.  If  therefore  a  man 
see  something  afar  off  and  obscurely,  although  no 
appellation  had  yet  been  given  to  anything,  he  will, 
notwithstanding,  have  the  same  idea  of  that  thing  for 
which  now,  by  imposing  a  name  on  it,  we  call  it  body. 
Again,  when,  by  coming  nearer,  he  sees  the  same  thing 
thus  and  thus,  now  in  one  place  and  now  in  another, 
he  will  have  a  new  idea  thereof,  namely,  that  for  which 


8  CONCERNING  BODY. 

we  now  call  such  a  thing  animated.  Thirdly,  when 
standing  nearer,  he  perceives  the  figure,  hears  the 
voice,  and  sees  other  things  which  are  signs  of  a  ra- 
tional mind,  he  has  a  third  idea,  though  it  have  yet  no 
appellation,  namely,  that  for  which  we  now  call  any- 
thing rational.  Lastly,  when,  by  looking  fully  and  dis- 
tinctly upon  it,  he  conceives  all  that  he  has  seen  as  one 
thing,  the  idea  he  has  now  is  compounded  of  his  for- 
mer ideas,  which  are  put  together  in  the  mind  in  the 
same  order  in  which  these  three  single  names,  body, 
animated,  rational,  are  in  speech  compounded  into  this 
one  name,  body-animated-rational,  or  man.  In  like 
manner,  of  the  several  conceptions  of  four  sides,  equal- 
ity of  sides,  and  right  angles,  is  compounded  the  con- 
ception of  a  square.  For  the  mind  may  conceive  a 
figure  of  four  sides  without  any  conception  of  their 
equality,  and  of  that  equality  without  conceiving  a 
right  angle;  and  may  join  together  all  these  single  con- 
ceptions into  one  conception  or  one  idea  of  a  square. 
And  thus  we  see  how  the  conceptions  of  the  mind  are 
compounded.  Again,  whosoever  sees  a  man  standing 
near  him,  conceives  the  whole  idea  of  that  man ;  and  if, 
as  he  goes  away,  he  follow  him  with  his  eyes  only,  he 
will  lose  the  idea  of  those  things  which  were  signs  of 
his  being  rational,  whilst,  nevertheless,  the  idea  of  a 
body-animated  remains  still  before  his  eyes,  so  that  the 
idea  of  rational  is  subtracted  from  the  whole  idea  of 
man,  that  is  to  say,  of  body-animated-rational,  and 
there  remains  that  of  body-animated ;  and  a  while 
after,  at  a  greater  distance,  the  idea  of  animated  will 
be  lost,  and  that  of  body  only  will  remain ;  so  that  at 
last,  when  nothing  at  all  can  be  seen,  the  whole  idea 
will  vanish  out  of  sight.     By  which  examples,  I  think, 


OF  PHILOSOPHY.  9 

it  is  manifest  enough  what  is  the  internal  ratiocination 
of  the  mind  without  words. 

We  must  not  therefore  think  that  computation,  that 
is,  ratiocination,  has  place  only  in  numbers,  as  if  man 
were  distinguished  from  other  living  creatures  (which 
is  said  to  have  been  the  opinion  of  Pythagoras)  by 
nothing  but  the  faculty  of  numbering;  for  magnitude, 
body,  motion,  time,  degrees  of  quality,  action,  concep- 
tion, proportion,  speech  and  names  (in  which  all  the 
kinds  of  philosophy  consist)  are  capable  of  addition 
and  substraction.  Now  such  things  as  we  add  or  sub- 
stract,  that  is,  which  we  put  into  an  account,  we  are.  said 
to  consider,  in  Greek  Xoyi&o-Bai,  in  which  language 
also  crvWoyc^eaOai signifies  to  compute,  reason,  or  reckon. 

4.  But  effects  and  the  appearances  of  things  to 
sense,  are  faculties  or  powers  of  bodies,  which  make 
us  distinguish  them  from  one  another ;  that  is  to  say, 
conceive  one  body  to  be  equal  or  unequal,  like  or  unlike 
to  another  body;  as  in  the  example  above,  when  by 
coming  near  enough  to  any  body,  we  perceive  the  mo- 
tion and  going  of  the  same,  we  distinguish  it  thereby 
from  a  tree,  a  column,  and  other  fixed  bodies;  and  so 
that  motion  or  going  is  the  property  thereof,  as  being 
proper  to  living  creatures,  and  a  faculty  by  which  they 
make  us  distinguish  them  from  other  bodies. 

5.  How  the  knowledge  of  any  effect  may  be  gotten 
from  the  knowledge  of  the  generation  thereof,  may 
easily  be  understood  by  the  example  of  a  circle :  for  if 
there  be  set  before  us  a  plain  figure,  having,  as  near  as 
may  be,  the  figure  of  a  circle,  we  cannot  possibly  per- 
ceive by  sense  whether  it  be  a  true  circle  or  no;  than 
which,  nevertheless,  nothing  is  more  easy  to  be  known 
to  him  that  knows  first  the  generation  of  the  pro- 
pounded figure.     For  let  it  be  known  that  the  figure 


io  CONCERNING  BODY. 

was  made  by  the  circumduction  of  a  body  whereof  one 
end  remained  unmoved,  and  we  may  reason  thus;  a 
body  carried  about,  retaining  always  the  same  length, 
applies  itself  first  to  one  radius,  then  to  another,  to  a 
third,  a  fourth,  and  successively  to  all ;  and,  therefore, 
the  same  length,  from  the  same  point,  toucheth  the 
circumference  in  every  part  thereof,  which  is  as  much 
as  to  say,  as  all  the  radii  are  equal.  We  know,  there- 
fore, that  from  such  generation  proceeds  a  figure,  from 
whose  one  middle  point  all  the  extreme  points  are 
reached  unto  by  equal  radii.  And  in  like  manner,  by 
knowing  first  what  figure  is  set  before  us,  we  may 
come  by  ratiocination  to  some  generation  of  the  same, 
though  perhaps  not  that  by  which  it  was  made,  yet 
that  by  which  it  might  have  been  made;  for  he  that 
knows  that  a  circle  has  the  property  above  declared, 
will  easily  know  whether  a  body  carried  about,  as  is 
said,  will  generate  a  circle  or  no. 

6.  The  end  or  scope  of  philosophy  is,  that  we  may 
make  use  to  our  benefit  of  effects  formerly  seen;  or 
that,  by  application  of  bodies  to  one  another,  we  may 
produce  the  like  effects  of  those  we  conceive  in  our 
mind,  as  far  forth  as  matter,  strength,  and  industry, 
will  permit,  for  the  commodity  of  human  life.  For 
the  inward  glory  and  triumph  of  mind  that  a  man  may 
have  for  the  mastering  of  some  difficult  and  doubtful 
matter,  or  for  the  discovery  of  some  hidden  truth,  is 
not  worth  so  much  pains  as  the  study  of  Philosophy 
requires;  nor  need  any  man  care  much  to  teach  an- 
other what  he  knows  himself,  if  he  think  that  will  be 
the  only  benefit  of  his  labour.  The  end  of  knowledge 
is  power;  and  the  use  of  theorems  (which,  among 
geometricians,  serve  for  the  finding  out  of  properties) 
is  for  the  construction  of  problems;  and,  lastly,  the 


OF  PHILOSOPHY.  n 

scope  of  all  speculation  is  the  performing  of  some 
action,  or  thing  to  be  done. 

7.  But  what  the  utility  of  philosophy  is,  especially 
of  natural  philosophy  and  geometry,  will  be  best  un- 
derstood by  reckoning  up  the  chief  commodities  of 
which  mankind  is  capable,  and  by  comparing  the  man- 
ner of  life  of  such  as  enjoy  them,  with  that  of  others 
which  want  the  same.  Now,  the  greatest  commodities 
of  mankind  are  the  arts ;  namely,  of  measuring  matter 
and  motion ;  of  moving  ponderous  bodies ;  of  architec- 
ture; of  navigation;  of  making  instruments  for  all 
uses ;  of  calculating  the  celestial  motions,  the  aspects  of 
the  stars,  and  the  parts  of  time;  of  geography,  &c. 
By  which  sciences,  how  great  benefits  men  receive  is 
more  easily  understood  than  expressed.  These  bene- 
fits are  enjoyed  by  almost  all  the  people  of  Europe,  by 
most  of  those  of  Asia,  and  by  some  of  Africa :  but  the 
Americans,  and  they  that  live  near  the  Poles,  do  totally 
want  them.  But  why?  Have  they  sharper  wits  than 
these?  Have  not  all  men  one  kind  of  soul,  and  the 
same  faculties  of  mind?  What,  then,  makes  this  dif- 
ference, except  philosophy?  Philosophy,  therefore,  is 
the  cause  of  all  these  benefits.  But  the  utility  of  moral 
and  civil  philosophy  is  to  be  estimated,  not  so  much 
by  the  commodities  we  have  by  knowing  these  sciences, 
as  by  the  calamities  we  receive  from  not  knowing  them. 
Now,  all  such  calamities  as  may  be  avoided  by  human 
industry,  arise  from  war,  but  chiefly  from  civil  war; 
for  from  this  proceed  slaughter,  solitude,  and  the  want 
of  all  things.  But  the  cause  of  war  is  not  that  men 
are  willing  to  have  it ;  for  the  will  has  nothing  for  ob- 
ject but  good,  at  least  that  which  seemeth  good.  Nor 
is  it  from  this,  that  men  know  not  that  the  effects  of 
war  are  evil ;  for  who  is  there  that  thinks  not  poverty 


12  CONCERNING  BODY. 

and  loss  of  life  to  be  great  evils?  The  cause,  there- 
fore, of  civil  war  is,  that  men  know  not  the  causes 
neither  of  war  nor  peace,  there  being  but  few  in  the 
world  that  have  learned  those  duties  which  unite  and 
keep  men  in  peace,  that  is  to  say,  that  have  learned  the 
rules  of  civil  life  sufficiently.  Now,  the  knowledge  of 
these  rules  is  moral  philosophy.  But  why  have  they 
not  learned  them,  unless  for  this  reason,  that  none 
hitherto  have  taught  them  in  a  clear  and  exact  method  ? 
For  what  shall  we  say?  Could  the  ancient  masters  of 
Greece,  Egypt,  Rome,  and  others,  persuade  the  un- 
skilful multitude  to  their  innumerable  opinions  con- 
cerning the  nature  of  their  gods,  which  they  themselves 
know  not  whether  they  were  true  or  false,  and  which 
were  indeed  manifestly  false  and  absurd;  and  could 
they  not  persuade  the  same  multitude  to  civil  duty,  if 
they  themselves  had  understood  it?  Or  shall  those 
few  writings  of  geometricians  which  are  extant,  be 
thought  sufficient  for  the  taking  away  of  all  contro- 
versy in  the  matters  they  treat  of,  and  shall  those  in- 
numerable and  huge  volumes  of  ethics  be  thought 
unsufficient,  if  what  they  teach  had  been  certain  and 
well  demonstrated?  What,  then,  can  be  imagined  to 
be  the  cause  that  the  writings  of  those  men  have 
increased  science,  and  the  writings  of  these  have  in- 
creased nothing  but  words,  saving  that  the  former  were 
written  by  men  that  knew,  and  the  latter  by  such  as 
know  not,  the  doctrine  they  taught  only  for  ostenta- 
tion of  their  wit  and  eloquence?  Nevertheless,  I  deny 
not  but  the  reading  of  some  such  books  is  very  delight- 
ful ;  for  they  are  most  eloquently  written,  and  contain 
many  clear,  wholesome  and  choice  sentences,  which  yet 
are  not  universally  true,  though  by  them  universally 
pronounced.     From  whence  it  comes  to  pass,  that  the 


OF  PHILOSOPHY.  13 

circumstances  of  times,  places,  and  persons  being 
being  changed,  they  are  no  less  frequently  made  use  of 
to  confirm  wicked  men  in  their  purposes,  than  to  make 
them  understand  the  precepts  of  civil  duties.  Now 
that  which  is  chiefly  wanting  in  them,  is  a  true  and  cer- 
tain rule  of  our  actions,  by  which  we  might  know 
whether  that  we  undertake  be  just  or  unjust.  For  it 
is  to  no  purpose  to  be  bidden  in  every  thing  to  do  right, 
before  there  be  a  certain  rule  and  measure  of  right 
established,  which  no  man  hitherto  hath  established. 
Seeing,  therefore,  from  the  not  knowing  of  civil  duties, 
that  is,  from  the  want  of  moral  science,  proceed  civil 
wars,  and  the  greatest  calamities  of  mankind,  we  may 
very  well  attribute  to  such  science  the  production  of 
the  contrary  commodities.  And  thus  much  is  suffi- 
cient, to  say  nothing  of  the  praises  and  other  content- 
ment proceeding  from  philosophy,  to  let  you  see  the 
utility  of  the  same  in  every  kind  thereof. 

8.  The  subject  of  Philosophy,  or  the  matter  it  treats 
of,  is  every  body  of  which  we  can  conceive  any  gen- 
eration, and  which  we  may,  by  any  consideration  there- 
of, compare  with  other  bodies,  or  which  is  capable  of 
composition  and  resolution ;  that  is  to  say,  every  body 
of  whose  generation  or  properties  we  can  have  any 
knowledge.  And  this  may  be  deduced  from  the  defi- 
nition of  philosophy,  whose  profession  it  is  to  search 
out  the  properties  of  bodies  from  their  generation,  or 
their  generation  from  their  properties ;  and,  therefore, 
where  there  is  no  generation  or  property,  there  is  no 
philosophy.  Therefore  it  excludes  Theology,  I  mean 
the  doctrine  of  God,  eternal,  ingenerable,  incomprehen- 
sible, and  in  whom  there  is  nothing  neither  to  divide 
nor  compound,  nor  any  generation  to  be  conceived. 

It  excludes  the  doctrine  of  angels,  and  all  such  things 


i4  CONCERNING  BODY. 

as  are  thought  to  be  neither  bodies  nor  properties  of 
bodies ;  there  being  in  them  no  place  neither  for  com- 
position nor  division,  nor  any  capacity  of  more  and 
less,  that  is  to  say,  no  place  for  ratiocination. 

It  excludes  history,  as  well  natural  as  political, 
though  most  useful  (nay  necessary)  to  philosophy; 
because  such  knowledge  is  but  experience,  or  author- 
ity, and  not  ratiocination. 

It  excludes  all  such  knowledge  as  is  acquired  by  Di- 
vine inspiration,  or  revelation,  as  not  derived  to  us  by 
reason,  but  by  Divine  grace  in  an  instant,  and,  as  it 
were,  by  some  sense  supernatural. 

It  excludes  not  only  all  doctrines  which  are  false, 
but  such  also  as  are  not  well-grounded ;  for  whatsoever 
we  know  by  right  ratiocination,  can  neither  be  false  nor 
doubtful;  and,  therefore,  astrology,  as  it  is  now  held 
forth,  and  all  such  divinations  rather  than  sciences,  are 
excluded. 

Lastly,  the  doctrine  of  God's  worship  is  excluded 
from  philosophy,  as  being  not  to  be  known  by  natural 
reason,  but  by  the  authority  of  the  Church;  and  as 
being  the  object  of  faith,  and  not  of  knowledge. 

9.  The  principal  parts  of  philosophy  are  two.  For 
two  chief  kinds  of  bodies,  and  very  different  from  one 
another,  offer  themselves  to  such  as  search  after  their 
generation  and  properties ;  one  whereof  being  the  work 
of  nature,  is  called  a  natural  body,  the  other  is  called  a 
commonwealth,  and  is  made  by  the  wills  and  agree- 
ment of  men.  And  from  these  spring  the  two  parts  of 
philosophy,  called  natural  and  civil.  But  seeing  that, 
for  the  knowledge  of  the  properties  of  a  common- 
wealth, it  is  necessary  first  to  know  the  dispositions, 
affections,  and  manners  of  men,  civil  philosophy  is 
again  commonly  divided  into  two  parts,  whereof  one, 


OF  PHILOSOPHY.  15 

which  treats  of  men's  dispositions  and  manners,  is 
called  ethics;  and  the  other,  which  takes  cognizance  of 
their  civil  duties,  is  called  politics,  or  simply  civil  phi- 
losophy.  In  the  first  place,  therefore  (after  I  have  set 
down  such  premises  as  appertain  to  the  nature  of 
philosophy  in  general),  I  will  discourse  of  bodies  nat- 
ural; in  the  second,  of  the  dispositions  and  manners  of 
men;  and  in  the  third,  of  the  civil  duties  of  subjects* 
10.  To  conclude;  seeing  there  may  be  many  who 
will  not  like  this  my  definition  of  philosophy,  and  will 
say,  that,  from  the  liberty  which  a  man  may  take  of  so 
defining  as  seems  best  to  himself,  he  may  conclude  any 
thing  from  any  thing  (though  I  think  it  no  hard  matter 
to  demonstrate  that  this  definition  of  mine  agrees  with 
the  sense  of  all  men)  ;  yet,  lest  in  this  point  there 
should  be  any  cause  of  dispute  betwixt  me  and  them, 
I  here  undertake  no  more  than  to  deliver  the  elements 
of  that  science  by  which  the  effects  of  anything  may 
be  found  out  from  the  known  generation  of  the  same, 
or  contrarily,  the  generation  from  the  effects ;  to  the 
end  that  they  who  search  after  other  philosophy,  may 
be  admonished  to  seek  it  from  other  principles. 

CHAPTER  II. 

OF  NAMES. 

I.  The  necessity  of  sensible  Moniments  or  Marks  for  the  help 
of  Memory :  a  Mark  defined. — 2.  The  necessity  of  Marks  for 
the  signification  of  the  conceptions  of  the  Mind. — 3.  Names 
supply  both  these  necessities. — 4.  The  Definition  of  a  Name. 
— 5.  Names  are  Signs  not  of  Things,  but  of  our  Cogitations. 
— 6.  What  it  is  we  give  Names  to. — 7.  Names  Positive  and 


*  For  lists  of  the  writings  of  Hobbes  on  ethics  and  on  pol- 
itics, cf.  p.  xviii. 


16  CONCERNING  BODY. 

Negative. — 8.  Contradictory  Names. — 9.  A  Common  Name. 
— 10.  Names  of  the  First  and  Second  Intention. — 11.  Uni- 
versal, Particular,  Individual,  and  Indefinite  Names. — 12. 
Names  Univocal  and  Equivocal. — 13.  Absolute  and  Relative 
Names. — 14.  Simple  and  Compounded  Names. — 15.  A  Pre- 
dicament described. — 16.  Some  things  to  be  noted  concern- 
ing Predicaments. 

CHAPTER  III. 

OF  PROPOSITION. 

I.  Divers  kinds  of  speech. — 2.  Proposition  denned. — 3.  Subject, 
predicate,  and  copula,  what  they  are ;  and  abstract  and  con- 
crete what.  The  use  and  abuse  of  names  abstract. — 5. 
Proposition,  universal  and  particular. — 6.  Affirmative  and 
negative. — 7.  True  and  false. — 8.  True  and  false  belongs  to 
speech,  and  not  to  things. — 9.  Proposition,  primary,  not  pri- 
mary, definition,  axiom,  petition. — 10.  Proposition,  necessary 
and  contingent. — II.  Categorical  and  hypothetical. — 12.  The 
same  proposition  diversely  pronounced. — 13.  Propositions 
that  may  be  reduced  to  the  same  categorical  proposition,  are 
equipollent. — 14.  Universal  propositions  converted  by  con- 
tradictory names,  are  equipollent. — 15.  Negative  propositions 
are  the  same,  whether  negation  be  before  or  after  the  copula. 
— 16.  Particular  propositions  simply  converted,  are  equipol- 
lent.— 17.  What  are  subaltern,  contrary,  subcontrary,  and 
contradictory  propositions. — 18.  Consequence,  what  it  is. — 19. 
Falsity  cannot  follow  from  truth. — 20.  How  one  proposition 
is  the  cause  of  another. 

CHAPTER  IV. 

OF  SYLLOGISM. 

I.  The  definition  of  syllogism. — 2.  In  a  syllogism  there  are  but 
three  terms. — 3.  Major,  minor,  and  middle  term;  also  major 
and  minor  proposition,  what  they  are. — 4.  The  middle  term 
in  every  syllogism  ought  to  be  determined  in  both  the  prop- 


OF  PHILOSOPHY.  17 

ositions  to  one  and  the  same  thing. — 5.  From  two  particular 
propositions  nothing  can  be  concluded. — 6.  A  syllogism  is 
the  collection  of  two  propositions  into  one  sum. — 7.  The  fig- 
ure of  a  syllogism,  what  it  is. — 8.  What  is  in  the  mind  an- 
swering to  a  syllogism. — 9.  The  first  indirect  figure,  how  it 
is  made. — 10.  The  second  indirect  figure,  how  made. — 11. 
How  the  third  indirect  figure  is  made. — 12.  There  are  many 
moods  in  every  figure,  but  most  of  them  useless  in  philos- 
ophy.—13.  An  hypothetical  syllogism  when  equipollent  to  a 
categorical. 

CHAPTER  V. 

OF  ERRING,  FALSITY,  AND  CAPTIONS. 

I.  Erring  and  falsity,  how  they  differ.  Error  of  the  mind  by 
itself  without  the  use  of  words,  how  it  happens.— 2.  A  seven- 
fold incoherency  of  names,  every  one  of  which  makes  always 
a  false  proposition.— 3.  Examples  of  the  first  manner  of  in- 
coherency.—4.  Of  the  second.— 5.  Of  the  third.— 6.  Of  the 
fourth.— 7.  Of  the  fifth.— 8.  Of  the  sixth.— 9.  Of  the  seventh. 
10.  Falsity  of  propositions  detected  by  resolving  the  terms 
with  definitions  continued  till  they  come  to  simple  names,  or 
names  that  are  the  most  general  of  their  kind. — 11.  Of  the 
fault  of  a  syllogism  consisting  of  the  implication  of  the  terms 
with  the  copula. — 12.  Of  the  fault  which  consists  in  equivo- 
cation.— 13.  Sophistical  captions  are  oftener  faulty  in  the 
matter  than  in  the  form  of  syllogisms. 

CHAPTER    VI. 

OF   METHOD. 

I.  Method  and  science  defined. — 2.  It  is  more  easily  known 
concerning  singular,  than  universal  things,  that  they  are ;  and 
contrarily,  it  is  more  easily  known  concerning  universal,  than 
singular  things,  why  they  are,  or  what  are  their  causes. — 
3. What  it  is  philosophers  seek  to  know. — 4.  The  first  part, 
by  which  principles  are  found  out,  is  purely  analytical. — 5. 
The  highest  causes,  and  most  universal  in  every  kind,  are 


18  CONCERNING  BODY. 

known  by  themselves. — 6.  Method  from  principles  found 
out,  tending  to  science  simply,  what  it  is. — 7.  That  method 
of  civil  and  natural  science,  which  proceeds  from  sense  to 
principles,  is  analytical;  and  again,  that,  which  begins  at 
principles,  is  synthetical. — 8.  The  method  of  searching  out, 
whether  any  thing  propounded  be  matter  or  accident. — 9. 
The  method  of  seeking  whether  any  accident  be  in  this,  or 
in  that  subject. — 10.  The  method  of  searching  after  the 
cause  of  any  effect  propounded. — II.  Words  serve  to  inven- 
tion, as  marks ;  to  demonstration,  as  signs. — 12.  The  method 
of  demonstration  is  synthetical. — 13.  Definitions  only  are  pri- 
mary and  universal  propositions. — 14.  The  nature  and  defi- 
nition of  a  definition.— 15.  The  properties  of  a  definition.— 
16.  The  nature  of  a  demonstration. — 17.  The  properties  of  a 
demonstration,  and  order  of  things  to  be  demonstrated. — 18. 
The  faults  of  a  demonstration. — 19.  Why  the  analytical 
method  of  geometricians  cannot  be  treated  of  in  this  place. 

I.  For  the  understanding  of  method,  it  will  be  nec- 
essary for  me  to  repeat  the  definition  of  philosophy,  de- 
livered above  (Chap.  1,  art.  2.)  in  this  manner,  Philos- 
ophy is  the  knowledge  we  acquire,  by  true  ratiocina- 
tion, of  appearances,  or  apparent  effects,  from  the 
knowledge  we  have  of  some  possible  production  or 
generation  of  the  same;  and  of  such  production,  as  has 
been  or  may  be,  from  the  knowledge  we  have  of  the 
effects.  Method,  therefore,  in  the  study  of  philoso- 
phy, is  the  shortest  way  of  finding  out  effects  by  their 
known  causes,  or  of  causes  by  their  known  effects. 
But  we  are  then  said  to  know  any  effect,  when  we 
know  that  there  be  causes  of  the  same,  and  in  what 
subject  those  causes  are,  and  in  what  subject  they  pro- 
duce  that  effect,  and  in  what  manner  they  work  the 
same.  And  this  is  the  science  of  causes,  or,  as  they 
call  it,  of  the  8l6tl.  All  other  science,  which  is  called 
the  on,  is  either  perception  by  sense,  or  the  imagina- 
tion, or  memory  remaining  after  such  perception. 


OF  METHOD.  19 

The  first  beginnings,  therefore,  of  knowledge,  are 
the  phantasms  of  sense  and  imagination ;  and  that  there 
be  such  phantasms  we  know  well  enough  by  nature; 
but  to  know  why  they  be,  or  from  what  causes  they 
proceed,  is  the  work  of  ratiocination;  which  consists 
(as  is  said  above,  in  the  1st  Chapter,  Art.  2)  in  com- 
position, and  division  or  resolution.  There  is  there- 
fore no  method,  by  which  we  find  out  the  causes  of 
things,  but  is  either  compositive  or  resolutive,  or  partly 
compositive,  and  partly  resolutive.  And  the  resolutive 
is  commonly  called  analytical  method,  as  the  composi- 
tive is  called  synthetical. 

2.*  It  is  common  to  all  sorts  of  method,  to  proceed 
from  known  things  to  unknown ;  and  this  is  manifest 
from  the  cited  definition  of  philosophy.  But  in  knowl- 
edge by  sense,  the  whole  object  is  more  known,  than 
any  part  thereof;  as  when  we  see  a  man,  the  concep- 
tion or  whole  idea  of  that  man  is  first  or  more  known, 
than  the  particular  ideas  of  his  being  Hgurate,  animate, 
and  rational;  that  is,  we  first  see  the  whole  man,  and 
take  notice  of  his  being,  before  we  observe  in  him 
those  other  particulars.  And  therefore  in  any  knowl- 
edge of  the  on,  or  that  any  thing  is,  the  beginning  of 
our  search  is  from  the  whole  idea;  and  contrarily,  in 
our  knowledge  of  the  Sioti,  or  of  the  causes  of  any 
thing,  that  is,  in  the  sciences,  we  have  more  knowledge 
of  the  causes  of  the  parts  than  of  the  whole.  For  the 
cause  of  the  whole  is  compounded  of  the  causes  of  the 
parts ;  but  it  is  necessary  that  we  know  the  things  that 
are  to  be  compounded,  before  we  can  know  the  whole 
compound.  Now,  by  parts,  I  do  not  here  mean  parts 
of  the  thing  itself,  but  parts  of  its  nature ;  as,  by  the 
parts  of  man,  I  do  not  understand  his  head,  his  shoul- 


20  CONCERNING  BODY. 

ders,  his  arms,  &c.  but  his  figure,  quantity,  motion, 
sense,  reason,  and  the  like ;  which  accidents  being  com- 
pounded or  put  together,  constitute  the  whole  nature 
of  man,  but  not  the  man  himself.  And  this  is  the 
meaning  of  that  common  saying,  namely,  that  some 
things  are  more  known  to  us,  others  more  known  to 
nature ;  for  I  do  not  think  that  they,  which  so  distin- 
guish, mean  that  something  is  known  to  nature,  which 
is  known  to  no  man;  and  therefore,  by  those  things, 
that  are  more  known  to  us,  we  are  to  understand  things 
we  take  notice  of  by  our  senses,  and,  by  more  known  to 
nature,  those  we  acquire  the  knowledge  of  by  reason ; 
for  in  this  sense  it  is,  that  the  whole,  that  is,  those 
things  that  have  universal  names,  (which,  for  brevity's 
sake,  I  call  universal)  are  more  known  to  us  than  the 
parts,  that  is,  such  things  as  have  names  less  universal, 
(which  I  therefore  call  singular)  ;  and  the  causes  of 
the  parts  are  more  known  to  nature  than  the  cause  of 
the  whole;  that  is,  universals  than  singulars. 

3.  In  the  study  of  philosophy,  men  search  after 
science  either  simply  or  indefinitely;  that  is,  to  know 
as  much  as  they  can,  without  propounding  to  them- 
selves any  limited  question;  or  they  enquire  into  the 
cause  of  some  determined  appearance,  or  endeavour  to 
find  out  the  certainty  of  something  in  question,  as  what 
is  the  cause  of  light,  of  heat,  of  gravity,  of  a  figure 
propounded,  and  the  like ;  or  in  what  subject  any  pro- 
pounded accident  is  inherent;  or  what  may  conduce 
most  to  the  generation  of  some  propounded  effect  from 
many  accidents;  or  in  what  manner  particular  causes 
ought  to  be  compounded  for  the  production  of  some 
certain  efifect.  Now,  according  to  this  variety  of 
things  in  question,  sometimes  the  analytical  method  is 
to  be  used,  and  sometimes  the  synthetical. 


OF  METHOD.  21 

4.  But  to  those  that  search  after  science  indefinitely, 
which  consists  in  the  knowledge  of  the  causes  of  all 
things,  as  far  forth  as  it  may  be  attained,  (and  the 
causes  of  singular  things  are  compounded  of  the  causes 
of  universal  or  simple  things)  it  is  necessary  that  they 
know  the  causes  of  universal  things,  or  of  such  acci- 
dents as  are  common  to  all  bodies,  that  is,  to  all  matter, 
before  they  can  know  the  causes  of  singular  things, 
that  is,  of  those  accidents  by  which  one  thing  is  distin- 
guished from  another.  And,  again,  they  must  know 
what  those  universal  things  are,  before  they  can  know 
their  causes.  Moreover,  seeing  universal  things  are 
contained  in  the  nature  of  singular  things,  the  knowl- 
edge of  them  is  to  be  acquired  by  reason,  that  is,  by 
resolution.  For  example,  if  there  be  propounded  a 
conception  or  idea  of  some  singular  thing,  as  of  a 
square,  this  square  is  to  be  resolved  into  a  plain,  termi- 
nated with  a  certain  number  of  equal  and  straight  lines 
and  right  angles.  For  by  this  resolution  we  have  these 
things  universal  or  agreeable  to  all  matter,  namely, 
line,  plain,  (which  contains  superficies)  terminated, 
angle,  straightness,  rectitude,  and  equality;  and  if  we 
can  find  out  the  causes  of  these,  we  may  compound 
them  altogether  into  the  cause  of  a  square.  Again,  if 
any  man  propound  to  himself  the  conception  of  gold, 
he  may,  by  resolving,  come  to  the  ideas  of  solid,  visible, 
heavy,  (that  is,  tending  to  the  centre  of  the  earth,  or 
downwards)  and  many  other  more  universal  than 
gold  itself;  and  these  he  may  resolve  again,  till  he 
come  to  such  things  as  are  most  universal.  And  in 
this  manner,  by  resolving  continually,  we  may  come  to 
know  what  those  things  are,  whose  causes  being  first 
known  severally,  and  afterwards  compounded,  bring 
us  to  the  knowledge  of  singular  things.     I  conclude, 


22  CONCERNING  BODY. 

therefore,  that  the  method  of  attaining  to  the  universal 
knowledge  of  things,  is  purely  analytical. 

5.     But  the  causes  of  universal  things  (of  those,  at 
least,  that  have  any  cause)  are  manifest  of  themselves, 
or  (as  they  say  commonly)  known  to  nature;  so  that 
they  need  no  method  at  all ;  for  they  have  all  but  one 
universal  cause,  which  is  motion.     For  the  variety  of 
all  figures  arises  out  of  the  variety  of  those  motions  by 
which  they  are  made;  and  motion  cannot  be  under- 
stood to  have  any  other  cause  besides  motion ;  nor  has 
the  variety  of  those  things  we  perceive  by  sense,  as  of 
colours,  sounds,  savours,  &c.  any  other  cause  than  mo- 
tion, residing  partly  in  the  objects  that  work  upon  our 
senses,  and  partly  in  ourselves,  in  such  manner,  as  that 
it  is  manifestly  some  kind  of  motion,  though  we  can- 
not, without  ratiocination,  come  to  know  what  kind. 
For  though  many  cannot  understand  till  it  be  in  some 
sort  demonstrated  to  them,  that  all  mutation  consists  in 
motion ;  yet  this  happens  not  from  any  obscurity  in  the 
thing  itself,  (for  it  is  not  intelligible  that  anything  can 
depart  either  from  rest,  or  from  the  motion  it  has,  ex- 
cept by  motion),  but  either  by  having  their  natural  dis- 
course corrupted  with  former  opinions  received  from 
their  masters,  or  else  for  this,  that  they  do  not  at  all 
bend  their  mind  to  the  enquiring  out  of  truth. 

6.  By  the  knowledge  therefore  of  universals,  and 
of  their  causes  (which  are  the  first  principles  by  which 
we  know  the  &0V1  of  things)  we  have  in  the  first  place 
their  definitions,  (which  are  nothing  but  the  explica- 
tion of  our  simple  conceptions.)  For  example,  he  that 
has  a  true  conception  of  place,  cannot  be  ignorant  of 
this  definition,  place  is  that  space  which  is  possessed  or 
ailed  adequately  by  some  body;  and  so,  he  that  con- 
ceives motion  aright,  cannot  but  know  that  motion  is 


OF  METHOD.  23 

the  privation  of  one  place,  and  the  acquisition  of  an- 
other. In  the  next  place,  we  have  their  generations  or 
descriptions;  as  (for  example)  that  a  line  is  made  by 
the  motion  of  a  point,  superficies  by  the  motion  of  a 
line,  and  one  motion  by  another  motion,  &c.  It  re- 
mains, that  we  enquire  what  motion  begets  such  and 
such  effects;  as,  what  motion  makes  a  straight  line, 
and  what  a  circular ;  what  motion  thrusts,  what  draws, 
and  by  what  way;  what  makes  a  thing  which  is  seen 
or  heard,  to  be  seen  or  heard  sometimes  in  one  manner, 
sometimes  in  another.  Now  the  method  of  this  kind 
of  enquiry,  is  compositive.  For  first,  we  are  to  observe 
what  effect  a  body  moved  produceth,  when  we  con- 
sider nothing  in  it  besides  its  motion ;  and  we  see  pres- 
ently that  this  makes  a  line,  or  length ;  next,  what  the 
motion  of  a  long  body  produces,  which  we  find  to  be 
superficies;  and  so  forwards,  till  we  see  what  the  ef- 
fects of  simple  motion  are;  and  then,  in  like  manner, 
we  are  to  observe  what  proceeds  from  the  addition, 
multiplication,  substraction,  and  division,  of  these  mo- 
tions, and  what  effects,  what  figures,  and  what  prop- 
erties, they  produce;  from  which  kind  of  contempla- 
tion sprung  that  part  of  philosophy  which  is  called 
geometry. 

From  this  consideration  of  what  is  produced  by 
simple  motion,  we  are  to  pass  to  the  consideration 
of  what  effects  one  body  moved  worketh  upon  another ; 
and  because  there  may  be  motion  in  all  the  several 
parts  of  a  body,  yet  so  as  that  the  whole  body  remain 
still  in  the  same  place,  we  must  enquire  first,  what 
motion  causeth  such  and  such  motion  in  the  whole,  that 
is,  when  one  body  invades  another  body  which  is  either 
at  rest  or  in  motion,  what  way,  and  with  what  swift- 
ness, the  invaded  body  shall  move;  and,  again,  what 


24  CONCERNING  BODY. 

motion  this  second  body  will  generate  in  a  third,  and 
so  forwards.  From  which  contemplation  shall  be 
drawn  that  part  of  philosophy  which  treats  of  motion. 

In  the  third  place  we  must  proceed  to  the  enquiry  of 
such  effects  as  are  made  by  the  motion  of  the  parts  of 
any  body,  as,  how  it  comes  to  pass,  that  things  when 
they  are  the  same,  yet  seem  not  to  be  the  same,  but 
changed.  And  here  the  things  we  search  after  are 
sensible  qualities,  such  as  light,  colour,  transparency, 
opacity,  sound,  odour,  savour,  heat,  cold,  and  the  like ; 
which  because  they  cannot  be  known  till  we  know  the 
causes  of  sense  itself,  therefore  the  consideration  of 
the  causes  of  seeing,  hearing,  smelling,  tasting  and 
touching,  belongs  to  this  third  place;  and  all  those 
qualities  and  changes,  above  mentioned,  are  to  be  re- 
ferred to  the  fourth  place;  which  two  considerations 
comprehend  that  part  of  philosophy  which  is  called 
physics.  And  in  these  four  parts  is  contained  whatso- 
ever in  natural  philosophy  may  be  explicated  by  dem- 
onstration, properly  so  called.  For  if  a  cause  were  to 
be  rendered  of  natural  appearances  in  special,  as,  what 
are  the  motions  and  influences  of  the  heavenly  bodies, 
and  of  their  parts,  the  reason  hereof  must  either  be 
drawn  from  the  parts  of  the  sciences  above  mentioned, 
or  no  reason  at  all  will  be  given,  but  all  left  to  uncer- 
tain conjecture. 

After  physics  we  must  come  to  moral  philosophy;  in 
which  we  are  to  consider  the  motions  of  the  mind, 
namely,  appetite,  aversion,  love,  benevolence,  hope, 
fear,  anger,  emulation,  envy,  &c. ;  what  causes  they 
have,  and  of  what  they  be  causes.  And  the  reason  why 
these  are  to  be  considered  after  physics  is,  that  they 
have  their  causes  in  sense  and  imagination,  which  are 
the  subject  of  physical  contemplation.    Also  the  reason, 


OF  METHOD.  25 

why  all  these  things  are  to  be  searched  after  in  the 
order  above-said,  is,  that  physics  cannot  be  understood, 
except  we  know  first  what  motions  are  in  the  smallest 
parts  of  bodies ;  nor  such  motion  of  parts,  till  we  know 
what  it  is  that  makes  another  body  move ;  nor  this,  till 
we  know  what  simple  motion  will  effect.  And  because 
all  appearance  of  things  to  sense  is  determined,  and 
made  to  be  of  such  and  such  quality  and  quantity  by 
compounded  motions,  every  one  of  which  has  a  certain 
degree  of  velocity,  and  a  certain  and  determined  way ; 
therefore,  in  the  first  place,  we  are  to  search  out  the 
ways  of  motion  simply  (in  which  geometry  consists)  ; 
next  the  ways  of  such  generated  motions  as  are  mani- 
fest ;  and,  lastly,  the  ways  of  internal  and  invisible  mo- 
tions (which  is  the  enquiry  of  natural  philosophers). 
And,  therefore,  they  that  study  natural  philosophy, 
study  in  vain,  except  they  begin  at  geometry ;  and  such 
writers  or  disputers  thereof,  as  are  ignorant  of  geom- 
etry, do  but  make  their  readers  and  hearers  lose  their 
time. 

7.  Civil  and  moral  philosophy  do  not  so  adhere 
to  one  another,  but  that  they  may  be  severed.  For  the 
causes  of  the  motions  of  the  mind  are  known,  not  only 
by  ratiocination,  but  also  by  the  experience  of  every 
man  that  takes  the  pains  to  observe  those  motions 
within  himself.  And,  therefore,  not  only  they  that 
have  attained  the  knowledge  of  the  passions  and  per- 
turbations of  the  mind,  by  the  synthetical  method,  and 
from  the  very  first  principles  of  philosophy,  may  by 
proceeding  in  the  same  way,  come  to  the  causes  and 
necessity  of  constituting  commonwealths,  and  to  get 
the  knowledge  of  what  is  natural  right,  and  what  are 
civil  duties;  and,  in  every  kind  of  government,  what 
are  the  rights  of  the  commonwealth,  and  all  other 


26  CONCERNING  BODY. 

knowledge  appertaining  to  civil  philosophy;  for  this 
reason,  tliat  the  principles  of  the  politics  consist  in  the 
knowledge  of  the  motions  of  the  mind,  and  the  knowl- 
edge of  these  motions  from  the  knowledge  of  sense  and 
imagination;  but  even  they  also  that  have  not  learned 
the  first  part  of  philosophy,  namely,  geometry  and 
physics,  may,  notwithstanding,  attain  the  principles 
of  civil  philosophy,  by  the  analytical  method.  For 
if  a  question  be  propounded,  as,  whether  such  an 
action  be  just  or  unjust;  if  that  unjust  be  resolved  into 
fact  against  law,  and  that  notion  law  into  the  command 
of  him  or  them  that  have  coercive  power;  and  that 
pozver  be  derived  from  the  wills  of  men  that  constitute 
such  power,  to  the  end  they  may  live  in  peace,  they 
may  at  last  come  to  this,  that  the  appetites  of  men  and 
the  passions  of  their  minds  are  such,  that,  unless  they 
be  restrained  by  some  power,  they  will  always  be 
making  war  upon  one  another;  which  may  be  known 
to  be  so  by  any  man's  experience,  that  will  but  examine 
his  own  mind.  And,  therefore,  from  hence  he  may 
proceed,  by  compounding,  to  the  determination  of  the 
justice  or  injustice  of  any  propounded  action.  So  that 
it  is  manifest,  by  what  has  been  said,  that  the  method 
of  philosophy,  to  such  as  seek  science  simply,  without 
propounding  to  themselves  the  solution  of  any  particu- 
lar question,  is  partly  analytical,  and  partly  synthetical ; 
namely,  that  which  proceeds  from  sense  to  the  invention 
of  principles,  analytical ;  and  the  rest  synthetical. 

8.  To  those  that  seek  the  cause  of  some  certain  and 
propounded  appearance  or  effect,  it  happens,  some- 
times, that  they  know  not  whether  the  thing,  whose 
cause  is  sought  after,  be  matter  or  body,  or  some  acci- 
dent of  a  body.  For  though  in  geometry,  when  the 
cause  is  sought  of  magnitude,  or  proportion,  or  figure, 


OF  METHOD.  27 

it  be  certainly  known  that  these  things,  namely  magni- 
tude, proportion,  and  figure,  are  accidents;  yet  in 
natural  philosophy,  where  all  questions  are  concerning 
the  causes  of  the  phantasms  of  sensible  things,  it  is  not 
so  easy  to  discern  between  the  things  themselves,  from 
which  those  phantasms  proceed,  and  the  appearances  of 
those  things  to  the  sense;  which  have  deceived  many, 
especially  when  the  phantasms  have  been  made  by 
light.  For  example,  a  man  that  looks  upon  the  sun, 
has  a  certain  shining  idea  of  the  magnitude  of  about  a 
foot  over,  and  this  he  calls  the  sun,  though  he  know 
the  sun  to  be  truly  a  great  deal  bigger;  and,  in  like 
manner,  the  phantasm  of  the  same  thing  appears  some- 
times round,  by  being  seen  afar  off,  and  sometimes 
square,  by  being  nearer.  Whereupon  it  may  well  be 
doubted,  whether  that  phantasm  be  matter,  or  some 
body  natural,  or  only  some  accident  of  a  body ;  in  the 
examination  of  which  doubt  we  may  use  this  method. 
The  properties  of  matter  and  accidents  already  found 
out  by  us,  by  the  synthetical  method,  from  their  defini- 
tions, are  to  be  compared  with  the  idea  we  have  before 
us;  and  if  it  agree  with  the  properties  of  matter  or 
body,  then  it  is  a  body;  otherwise  it  is  an  accident. 
Seeing,  therefore,  matter  cannot  by  any  endeavor  of 
ours  be  either  made  or  destroyed,  or  increased,  or  di- 
minished, or  moved  out  of  its  place,  whereas  that  idea 
appears,  vanishes,  is  increased  and  diminished,  and 
moved  hither  and  thither  at  pleasure ;  we  may  certainly 
conclude  that  it  is  not  a  body,  but  an  accident  only.  And 
this  method  is  synthetical. 

9.  But  if  there  be  a  doubt  made  concerning  the  sub- 
ject of  any  known  accident  (for  this  may  be  doubted 
sometimes,  as  in  the  precedent  example,  doubt  may  be 
made   in  what   subject  that   splendour   and  apparent 


28  CONCERNING  BODY. 

magnitude  of  the  sun  is),  then  our  enquiry  must  pro- 
ceed in  this  manner.  First,  matter  in  general  must  be 
divided  into  parts,  as,  into  object,  medium,  and  the 
sentient  itself,  or  such  other  parts  as  seem  most  con- 
formable to  the  thing  propounded.  Next,  these  parts 
are  severally  to  be  examined  how  they  agree  with  the 
definition  of  the  subject;  and  such  of  them  as  are  not 
capable  of  that  accident  are  to  be  rejected.  For  ex- 
ample, if  by  any  true  ratiocination  the  sun  be  found 
to  be  greater  than  its  apparent  magnitude,  then  that 
magnitude  is  not  in  the  sun;  if  the  sun  be  in  one 
determined  straight  line,  and  one  determined  distance, 
and  the  magnitude  and  splendour  be  seen  in  more  lines 
and  distances  than  one,  as  it  is  in  reflection  or  refrac- 
tion, then  neither  that  splendour  nor  apparent  magni- 
tude are  in  the  sun  itself,  and,  therefore,  the  body  of  the 
sun  cannot  be  the  subject  of  that  splendour  and  magni- 
tude. And  for  the  same  reasons  the  air  and  other  parts 
will  be  rejected,  till  at  last  nothing  remain  which  can  be 
the  subject  of  that  splendour  and  magnitude  but  the 
sentient  itself.  And  this  method,  in  regard  the  subject 
is  divided  into  parts,  is  analytical ;  and  in  regard  the 
properties,  both  of  the  subject  and  accident,  are  com- 
pared with  the  accident  concerning  whose  subject  the 
enquiry  is  made,  it  is  synthetical. 

10.  But  when  we  seek  after  the  cause  of  any  pro- 
pounded effect,  we  must  in  the  first  place  get  into  our 
mind  an  exact  notion  or  idea  of  that  which  we  call 
cause,  namely,  that  a  cause  is  the  sum  or  aggregate  of 
all  such  accidents,  both  in  the  agents  and  the  patient, 
as  concur  to  the  producing  of  the  effect  propounded; 
all  of  which  existing  together,  it  cannot  be  understood 
but  that  the  effect  exist eth  with  them:  or  that  it  can 
possibly  exist  if  any  one  of  them  be  absent.    This  being 


OF  METHOD.  29 

known,  in  the  next  place  we  must  examine  singly  every 
accident  that  accompanies  or  precedes  the  effect,  as  far 
forth  as  it  seems  to  conduce  in  any  manner  to  the  pro- 
duction of  the  same,  and  see  whether  the  propounded 
effect  may  be  conceived  to  exist,  without  the  existence 
of  any  of  those  accidents ;  and  by  this  means  separate 
such  accidents,  as  do  not  concur,  from  such  as  concur 
to  produce  the  said  effect ;  which  being  done,  we  are  to 
put  together  the  concurring  accidents,  and  consider 
whether  we  can  possibly  conceive,  that  when  these  are 
all  present,  the  effect  propounded  will  not  follow ;  and 
if  it  be  evident  that  the  effect  will  follow,  then  that 
aggregate  of  accidents  is  the  entire  cause,  otherwise 
not ;  but  we  must  still  search  out  and  put  together  other 
accidents.  For  example,  if  the  cause  of  light  be  pro- 
pounded to  be  sought  out ;  first,  we  examine  things 
without  us,  and  find  that  whensoever  light  appears, 
there  is  some  principal  object,  as  it  were  the  fountain 
of  light,  without  which  we  cannot  have  any  perception 
of  light ;  and,  therefore,  the  concurrence  of  that  object 
is  necessary  to  the  generation  of  light.  Next  we  con- 
sider the  medium,  and  find,  that  unless  it  be  disposed 
in  a  certain  manner,  namely,  that  it  be  transparent, 
though  the  object  remain  the  same,  yet  the  effect  wTill 
not  follow ;  and,  therefore,  the  concurrence  of  trans- 
parency is  also  necessary  to  the  generation  of  light. 
Thirdly,  we  observe  our  own  body,  and  find  that  by 
the  indisposition  of  the  eyes,  the  brain,  the  nerves,  and 
the  heart,  that  is,  by  obstructions,  stupidity,  and  de- 
bility we  are  deprived  of  light,  so  that  a  fitting  disposi- 
tion of  the  organs  to  receive  impressions  from  without 
is  likewise  a  necessary  part  of  the  cause  of  light. 
Again,  of  all  the  accidents  inherent  in  the  object,  there 
is  none  that  can  conduce  to  the  effecting  of  light,  but 


30  CONCERNING  BODY. 

only  action  (or  a  certain  motion),  which  cannot  be 
conceived  to  be  wanting,  whensoever  the  effect  is 
present ;  for,  that  anything  may  shine,  it  is  not  requisite 
that  it  be  of  such  or  such  magnitude  or  figure,  or  that 
the  whole  body  of  it  be  moved  out  of  the  place  it  is  in 
(unless  it  may  perhaps  be  said,  that  in  the  sun,  or  other 
body,  that  which  causes  light  is  the  light  it  hath  in 
itself;  which  yet  is  but  a  trifling  exception,  seeing 
nothing  is  meant  thereby  but  the  cause  of  light;  as 
if  any  man  should  say  that  the  cause  of  light  is 
that  in  the  sun  which  produceth  it)  ;  it  remains, 
therefore,  that  the  action,  by  which  light  is  gen- 
erated, is  motion  only  in  the  parts  of  the  object.  Which 
being  understood,  we  may  easily  conceive  what  it  is  the 
medium  contributes,  namely,  the  continuation  of  that 
motion  to  the  eye ;  and,  lastly,  what  the  eye  and  the 
rest  of  the  organs  of  the  sentient  contribute,  namely, 
the  continuation  of  the  same  motion  to  the  last  organ 
of  sense,  the  heart.  And  in  this  manner  the  cause  of 
light  may  be  made  up  of  motion  continued  from  the 
original  of  the  same  motion,  to  the  original  of  vital 
motion,  light  being  nothing  but  the  alteration  of  vital 
motion,  made  by  the  impression  upon  it  of  motion 
continued  from  the  object.  But  I  give  this  only  for  an 
example,  for  I  shall  speak  more  at  large  of  light,  and 
the  generation  of  it,  in  its  proper  place.  In  the  mean 
time  it  is  manifest,  that  in  the  searching  out  of  causes, 
there  is  need  partly  of  the  analytical,  and  partly  of  the 
synthetical  method ;  of  the  analytical,  to  conceive  how 
circumstances  conduce  severally  to  the  production  of 
effects ;  and  of  the  synthetical,  for  the  adding  together 
and  compounding  of  what  they  can  effect  singly  by 
themselves.  And  thus  much  may  serve  for  the  method 
of  invention.     It  remains  that  I  speak  of  the  method 


OF  METHOD.  31 

of  teaching,  that  is,  of  demonstration,  and  of  the  means 
by  which  we  demonstrate. 

11.  In  the  method  of  invention,  the  use  of  words 
consists  in  this,  that  they  may  serve  for  marks,  by 
which,  whatsoever  we  have  found  out  may  be  recalled 
to  memory;  for  without  this  all  our  inventions  perish, 
nor  will  it  be  possible  for  us  to  go  on  from  principles 
beyond  a  syllogism  or  two,  by  reason  of  the  weakness 
of  memory.  For  example,  if  any  man,  by  considering 
a  triangle  set  before  him,  should  find  that  all  its  angles 
together  taken  are  equal  to  two  right  angles,  and  that 
by  thinking  of  the  same  tacitly,  without  any  use  of 
words  either  understood  or  expressed;  and  it  should 
happen  afterwards  that  another  triangle,  unlike  the 
former,  or  the  same  in  different  situation,  should  be 
offered  to  his  consideration,  he  would  not  know  readily 
whether  the  same  property  were  in  this  last  or  no,  but 
would  be  forced,  as  often  as  a  different  triangle  were 
brought  before  him  (and  the  difference  of  triangles  is 
infinite)  to  begin  his  contemplation  anew;  which  he 
would  have  no  need  to  do  if  he  had  the  use  of  names, 
for  every  universal  name  denotes  the  conceptions  we 
have  of  infinite  singular  things.  Nevertheless,  as  I  said 
above,  they  serve  as  marks  for  the  help  of  our  memory, 
whereby  we  register  to  ourselves  our  own  inventions; 
but  not  as  signs  by  which  we  declare  the  same  to 
others ;  so  that  a  man  may  be  a  philosopher  alone  by 
himself,  without  any  master;  Adam  had  this  capacity. 
But  to  teach,  that  is,  to  demonstrate,  supposes  two  at 
the  least,  and  syllogistical  speech. 

12.  And  seeing  teaching  is  nothing  but  leading 
the  mind  of  him  we  teach,  to  the  knowledge  of  our  in- 
ventions, in  that  track  by  which  we  attained  the  same 
with  our  own  mind;  therefore,  the  same  method  that 


32  CONCERNING  BODY. 

served  for  our  invention,  will  serve  also  for  demon- 
stration to  others,  saving  that  we  omit  the  first  part  of 
method  which  proceeded  from  the  sense  of  things  to 
universal  principles,  which,  because  they  are  principles, 
cannot  be  demonstrated;  and  seeing  they  are  known 
by  nature,  (as  was  said  above  in  the  5th  article)  they 
need  no  demonstration,  though  they  need  explication. 
The  whole  method,  therefore,  of  demonstration,  is 
synthetical,  consisting  of  that  order  of  speech  which 
begins  from  primary  or  most  universal  propositions, 
which  are  manifest  of  themselves,  and  proceeds  by  a 
perpetual  composition  of  propositions  into  syllogisms, 
till  at  last  the  learner  understand  the  truth  of  the  con- 
clusion sought  after. 

13.  Now,  such  principles  are  nothing  but  defi- 
nitions, whereof  there  are  two  sorts ;  one  of  names, 
that  signify  such  things  as  have  some  conceivable 
cause,  and  another  of  such  names  as  signify  things  of 
which  we  can  conceive  no  cause  at  all.  Names  of  the 
former  kind  are,  body,  or  matter,  quantity,  or  exten- 
sion, motion,  and  whatsoever  is  common  to  all  matter. 
Of  the  second  kind,  are  such  a  body,  such  and  so  great 
motion,  so  great  magnitude,  such  figure,  and  whatso- 
ever we  can  distinguish  one  body  from  another  by. 
And  names  of  the  former  kind  are  well  enough  defined, 
when,  by  speech  as  short  as  may  be,  we  raise  in  the 
mind  of  the  hearer  perfect  and  clear  ideas  or  concep- 
tions of  the  things  named,  as  when  we  define  motion 
to  be  the  leaving  of  one  place,  and  the  acquiring  of 
another  continually ;  for  though  no  thing  moved,  nor 
any  cause  of  motion  be  in  that  definition,  yet,  at  the 
hearing  of  that  speech,  there  will  come  into  the  mind 
of  the  hearer  an  idea  of  motion  clear  enough.  But 
definitions  of  things,  which  may  be  understood  to  have 


OF  METHOD.  33 

some  cause,  must  consist  of  such  names  as  express  the 
cause  or  manner  of  their  generation,  as  when  we  define 
a  circle  to  be  a  figure  made  by  the  circumduction  of  a 
straight  line  in  a  plane,  &c.  Besides  definitions,  there 
is  no  other  proposition  that  ought  to  be  called  primary, 
or  (according  to  severe  truth)  be  received  into  the 
number  of  principles.  For  those  axioms  of  Euclid, 
seeing  they  may  be  demonstrated,  are  no  principles  of 
demonstration,  though  they  have  by  the  consent  of  all 
men  gotten  the  authority  of  principles,  because  they 
need  not  be  demonstrated.  Also,  those  petitions,  or 
postulata,  (as  they  call  them)  though  they  be  princi- 
ples, yet  they  are  not  principles  of  demonstration,  but 
of  construction  only;  that  is,  not  of  science,  but  of 
power;  or  (which  is  all  one)  not  of  theorems,  which 
are  speculations,  but  of  problems,  which  belong  to  prac- 
tice, or  the  doing  of  something.  But  as  for  those  com- 
mon received  opinions,  Nature  abhors  vacuity,  Nature 
doth  nothing  in  vain,  and  the  like,  which  are  neither 
evident  in  themselves,  nor  at  all  to  be  demonstrated, 
and  which  are  oftener  false  than  true,  they  are  much 
less  to  be  acknowledged  for  principles. 

To  return,  therefore,  to  definitions;  the  reason  why 
I  say  that  the  cause  and  generation  of  such  things,  as 
have  any  cause  or  generation,  ought  to  enter  into  their 
definitions,  is  this.  The  end  of  science  is  the  demon- 
stration of  the  causes  and  generation  of  things ;  which 
if  they  be  not  in  the  definitions,  they  cannot  be  found 
in  the  conclusion  of  the  first  syllogism,  that  is  made 
from  those  definitions;  and  if  they  be  not  in  the  first 
conclusion,  they  will  not  be  found  in  any  further  con- 
clusion deduced  from  that ;  and,  therefore,  by  proceed- 
ing in  this  manner,  we  shall  never  come  to  science; 


34  CONCERNING  BODY. 

which  is  against  the  scope  and  intention  of  demonstra- 
tion. 

14.  Now,  seeing  definitions  (as  I  have  said)  are 
principles,  or  primary  propositions,  they  are  therefore 
speeches ;  and  seeing  they  are  used  for  the  raising  of  an 
idea  of  some  thing  in  the  mind  of  the  learner,  whenso- 
ever that  thing  has  a  name,  the  definition  of  it  can  be 
nothing  but  the  explication  of  that  name  by  speech; 
and  if  that  name  be  given  it  for  some  compounded  con- 
ception, the  definition  is  nothing  but  a  resolution  of 
that  name  into  its  most  universal  parts.  As  when  we 
define  man,  saying  man  is  a  body  animated,  sentient, 
rational,  those  names,  body  animated,  &c,  are  parts  of 
that  whole  name  man;  so  that  definitions  of  this  kind 
always  consist  of  genus  and  difference;  the  former 
names  being  all,  till  the  last,  general;  and  the  last  of 
all,  difference.  But  if  any  name  be  the  most  universal 
in  its  kind,  then  the  definition  of  it  cannot  consist  of 
genus  and  difference,  but  is  to  be  made  by  such  circum- 
locution, as  best  explicateth  the  force  of  that  name. 
Again,  it  is  possible,  and  happens  often,  that  the  genns 
and  difference  are  put  together,  and  yet  make  no  defini- 
tion; as  these  words,  a  straight  line,  contain  both  the 
genus  and  difference;  but  are  not  a  definition,  unless 
we  should  think  a  straight  line  may  be  thus  defined,  a 
straight  line  is  a  straight  line:  and  yet  if  there  were 
added  another  name,  consisting  of  different  words,  but 
signifying  the  same  thing  which  these  signify,  then 
these  might  be  the  definition  of  that  name.  From  what 
has  been  said,  it  may  be  understood  how  a  definition 
ought  to  be  defined,  namely,  that  it  is  a  proposition, 
whose  predicate  resolves  the  subject,  when  it  may;  and 
zvhen  it  may  not,  it  exemplifies  the  same. 
15.     The  properties  of  a  definition  are: 


OF  METHOD.  35 

First,  that  it  takes  away  equivocation,  as  also  all  that 
multitude  of  distinctions,  which  are  used  by  such  as 
think  they  may  learn  philosophy  by  disputation.  For 
the  nature  of  a  definition  is  to  define,  that  is,  to  deter- 
mine the  signification  of  the  defined  name,  and  to  pare 
from  it  all  other  signification  besides  what  is  contained 
in  the  definition  itself;  and  therefore  one  definition 
does  as  much,  as  all  the  distinctions  (how  many  so- 
ever) that  can  be  used  about  the  name  defined. 

Secondly,  that  it  gives  an  universal  notion  of  the 
thing  defined,  representing  a  certain  universal  picture 
thereof,  not  to  the  eye,  but  to  the  mind.  For  as  when 
one  paints  a  man,  he  paints  the  image  of  some  man; 
so  he,  that  defines  the  name  man,  makes  a  representa- 
tion of  some  man  to  the  mind. 

Thirdly,  that  it  is  not  necessary  to  dispute  whether 
definitions  are  to  be  admitted  or  no.  For  when  a 
master  is  instructing  his  scholar,  if  the  scholar  under- 
stand all  the  parts  of  the  thing  defined,  which  are  re- 
solved in  the  definition,  and  yet  will  not  admit  of  the 
definition,  there  needs  no  further  controversy  betwixt 
them,  it  being  all  one  as  if  he  refused  to  be  taught. 
But  if  he  understand  nothing,  then  certainly  the  defi- 
nition is  faulty;  for  the  nature  of  a  definition  consists 
in  this,  that  it  exhibit  a  clear  idea  of  the  thing  defined ; 
and  principles  are  either  known  by  themselves,  or  else 
they  are  not  principles. 

Fourthly,  that,  in  philosophy,  definitions  are  before 
defined  names.  For  in  teaching  philosophy,  the  first 
beginning  is  from  definitions ;  and  all  progression  in 
the  same,  till  we  come  to  the  knowledge  of  the  thing 
compounded,  is  compositive.  Seeing,  therefore,  defi- 
nition is  the  explication  of  a  compounded  name  by 
resolution,  and  the  progression  is  from  the  parts  to  the 


36  CONCERNING  BODY. 

compound,  definitions  must  be  understood  before  com- 
pounded names;  nay,  when  the  names  of  the  parts  of 
any  speech  be  explicated,  it  is  not  necessary  that  the 
definition  should  be  a  name  compounded  of  them.  For 
example,  when  these  names,  equilateral,  quadrilateral, 
right-angled,  are  sufficiently  understood,  it  is  not  neces- 
sary in  geometry  that  there  should  be  at  all  such  a 
name  as  square;  for  defined  names  are  received  in 
philosophy  for  brevity's  sake  only. 

Fifthly,  that  compounded  names,  which  are  defined 
one  way  in  some  one  part  of  philosophy,  may  in  an- 
other part  of  the  same  be  otherwise  defined ;  as  a  para- 
bola and  an  hyperbole  have  one  definition  in  geometry, 
and  another  in  rhetoric;  for  definitions  are  instituted 
and  serve  for  the  understanding  of  the  doctrine 
which  is  treated  of.  And,  therefore,  as  in  one  part  of 
philosophy,  a  definition  may  have  in  it  some  one  fit 
name  for  the  more  brief  explanation  of  some  proposi- 
tion in  geometry;  so  it  may  have  the  same  liberty  in 
other  parts  of  philosophy ;  for  the  use  of  names  is  par- 
ticular (even  where  many  agree  to  the  settling  of 
them)  and  arbitrary. 

Sixthly,  that  no  name  can  be  defined  by  any  one 
word ;  because  no  one  word  is  sufficient  for  the  resolv- 
ing of  one  or  more  words. 

Seventhly,  that  a  defined  name  ought  not  to  be  re- 
peated in  the  definition.  For  a  defined  name  is  the 
whole  compound,  and  a  definition  is  the  resolution  of 
that  compound  into  parts ;  but  no  total  can  be  part  of 
itself. 

1 6.  Any  two  definitions,  that  may  be  compounded 
into  a  syllogism,  produce  a  conclusion ;  which,  because 
it  is  derived  from  principles,  that  is,  from  definitions,  is 
said  to  be  demonstrated;  and  the  derivation  or  com- 


OF  METHOD.  37 

position  itself  is  called  a  demonstration.  In  like  man- 
ner, if  a  syllogism  be  made  of  two  propositions,  whereof 
one  is  a  definition,  the  other  a  demonstrated  conclusion, 
or  neither  of  them  is  a  definition,  but  both  formerly 
demonstrated,  that  syllogism  is  also  called  a  demon- 
stration, and  so  successively.  The  definition  therefore 
of  a  demonstration  is  this,  a  demonstration  is  a  syllo- 
gism, or  series  of  syllogisms,  derived  and  continued, 
from  the  definitions  of  names,  to  the  last  conclusion. 
And  from  hence  it  may  be  understood,  that  all  true 
ratiocination,  which  taketh  its  beginning  from  true 
principles,  produceth  science,  and  is  true  demonstra- 
tion. For  as  for  the  original  of  the  name,  although 
that,  which  the  Greeks  called  AiroSi^,  and  the 
Latins  demonstratio,  was  understood  by  them  for  that 
sort  only  of  ratiocination,  in  which,  by  the  describing 
of  certain  lines  and  figures,  they  placed  the  thing  they 
were  to  prove,  as  it  were  before  men's  eyes,  which  is 
properly  aTro&uKvvciv ,  or  to  shezv  by  the  figure;  yet 
they  seem  to  have  done  it  for  this  reason,  that  unless 
it  were  in  geometry,  (in  which  only  there  is  place  for 
such  figures)  there  was  no  ratiocination  certain,  and 
ending  in  science,  their  doctrines  concerning  all  other 
things  being  nothing  but  controversy  and  clamour; 
which,  nevertheless,  happened,  not  because  the  truth  to 
which  they  pretended  could  not  be  made  evident  with- 
out figures,  but  because  they  wanted  true  principles, 
from  which  they  might  derive  their  ratiocination ;  and, 
therefore,  there  is  no  reason  but  that  if  true  definitions 
were  premised  in  all  sorts  of  doctrines,  the  demonstra- 
tions also  would  be  trne. 

17.     It  is  proper  to  methodical  demonstration, 
First,  that  there  be  a  true  succession  of  one  reason  to 


38  CONCERNING  BODY. 

another,  according  to  the  rules  of  syllogizing  delivered 
above. 

Secondly,  that  the  premises  of  all  syllogisms  be 
demonstrated  from  the  first  definitions. 

Thirdly,  that  after  definitions,  he  that  teaches  or 
demonstrates  any  thing,  proceed  in  the  same  method 
by  which  he  found  it  out ;  namely,  that  in  the  first  place 
those  things  be  demonstrated,  which  immediately  suc- 
ceed to  universal  definitions  (in  which  is  contained  that 
part  of  philosophy  which  is  called  philosophia  prima). 
Next,  those  things  which  may  be  demonstrated  by 
simple  motion  (in  which  geometry  consists).  After 
geometry,  such  things  as  may  be  taught  or  shewed  by 
manifest  action,  that  is,  by  thrusting  from,  or  pulling 
towards.  And  after  these,  the  motion  or  mutation  of 
the  invisible  parts  of  things,  and  the  doctrine  of  sense 
and  imaginations,  and  of  the  internal  passions,  espe- 
cially those  of  men,  in  which  are  comprehended  the 
grounds  of  civil  duties,  or  civil  philosophy;  which 
takes  up  the  last  place.  And  that  this  method  ought 
to  be  kept  in  all  sorts  of  philosophy,  is  evident  from 
hence,  that  such  things  as  I  have  said  are  to  be  taught 
last,  cannot  be  demonstrated,  till  such  as  are  pro- 
pounded to  be  first  treated  of,  be  fully  understood.  Of 
which  method  no  other  example  can  be  given,  but  that 
treatise  of  the  elements  of  philosophy,  which  I  shall 
begin  in  the  next  chapter,  and  continue  to  the  end  of 
the  work. 

1 8.  Besides  those  paralogisms,  whose  fault  lies 
either  in  the  falsity  of  the  premises,  or  the  want  of  true 
composition,  of  which  I  have  spoken  in  the  precedent 
chapter,  there  are  two  more,  which  are  frequent  in 
demonstration ;  one  whereof  is  commonly  called  petitio 
principii;  the  other  is  the  supposing  of  a  false  cause; 


OF  METHOD.  39 

and  these  do  not  only  deceive  unskilful  learners,  but 
sometimes  masters  themselves,  by  making  them  take 
that  for  well  demonstrated,  which  is  not  demonstrated 
at  all.  Petitio  principii  is,  when  the  conclusion  to  be 
proved  is  disguised  in  other  words,  and  put  for  the 
definition  or  principle  from  whence  it  is  to  be  demon- 
strated ;  and  thus,  by  putting  for  the  cause  of  the  thing 
sought,  either  the  thing  itself  or  some  effect  of  it,  they 
make  a  circle  in  their  demonstration.  As  for  example, 
he  that  would  demonstrate  that  the  earth  stands  still  in 
the  centre  of  the  world,  and  should  suppose  the  earth's 
gravity  to  be  the  cause  thereof,  and  define  gravity  to 
be  a  quality  by  which  every  heavy  body  tends  towards 
the  centre  of  the  world,  would  lose  his  labour ;  for  the 
question  is,  what  is  the  cause  of  that  quality  in  the 
earth?  and,  therefore,  he  that  supposes  gravity  to  be 
the  cause,  puts  the  thing  itself  for  its  own  cause. 

Of  a  false  cause  I  find  this  example  in  a  certain 
treatise  where  the  thing  to  be  demonstrated  is  the 
motion  of  the  earth.  He  begins,  therefore,  with  this, 
that  seeing  the  earth  and  the  sun  are  not  always  in  the 
same  situation,  it  must  needs  be  that  one  of  them  be 
locally  moved,  which  is  true ;  next,  he  affirms  that  the 
vapours  which  the  sun  raises  from  the  earth  and  sea, 
are,  by  reason  of  this  motion,  necessarily  moved,  which 
also  is  true ;  from  whence  he  infers  the  winds  are  made, 
and  this  may  pass  for  granted ;  and  by  these  winds  he 
says,  the  waters  of  the  sea  are  moved,  and  by  their 
motion  the  bottom  of  the  sea,  as  if  it  were  beaten  for- 
wards, moves  round ;  and  let  this  also  be  granted ; 
wherefore,  he  concludes,  the  earth  is  moved ;  which  is, 
nevertheless,  a  paralogism.  For,  if  that  wind  were  the 
cause  why  the  earth  was,  from  the  beginning,  moved 
round,  and  the  motion  either  of  the  sun  or  the  earth 


40  CONCERNING  BODY. 

were  the  cause  of  that  wind,  then  the  motion  of  the 
sun  or  the  -earth  was  before  the  wind  itself ;  and  if  the 
earth  were  moved,  before  the  wind  was  made,  then 
the  wind  could  not  be  the  cause  of  the  earth's  revolu- 
tion; but,  if  the  sun  were  moved,  and  the  earth  stand 
still,  then  it  is  manifest  the  earth  might  remain  un- 
moved, notwithstanding  that  wind;  and  therefore  that 
motion  was  not  made  by  the  cause  which  he  allegeth. 
But  paralogisms  of  this  kind  are  very  frequent  among 
the  writers  of  physics,  though  none  can  be  more  elabo- 
rate than  this  in  the  example  given. 

19.  It  may  to  some  men  seem  pertinent  to  treat  in 
this  place  of  that  art  of  the  geometricians,  which  they 
call  logistica,  that  is,  the  art,  by  which,  from  supposing 
the  thing  in  question  to  be  true,  they  proceed  by  ratioci- 
nation, till  either  they  come  to  something  known,  by 
which  they  may  demonstrate  the  truth  of  the  thing 
sought  for ;  or  to  something  which  is  impossible,  from 
whence  they  collect  that  to  be  false,  which  they  sup- 
posed true.  But  this  art  cannot  be  explicated  here,  for 
this  reason,  that  the  method  of  it  can  neither  be  prac- 
tised, nor  understood,  unless  by  such  as  are  well  versed 
in  geometry ;  and  among  geometricians  themselves, 
they,  that  have  most  theorems  in  readiness,  are  the 
most  ready  in  the  use  of  this  logistica;  so  that,  indeed, 
it  is  not  a  distinct  thing  for  geometry  itself ;  for  there 
are,  in  the  method  of  it,  three  parts;  the  first  whereof 
consists  in  the  finding  out  of  equality  betwixt  known 
and  unknown  things,  which  they  call  equation ;  and  this 
equation  cannot  be  found  out,  but  by  such  as  know 
perfectly  the  nature,  properties,  and  transpositions  of 
proportion,  as  also  the  addition,  subtraction,  multiplica- 
tion, and  division  of  lines  and  superficies,  and  the  ex- 
traction of  roots ;  which  are  the  parts  of  no  mean  geo- 


OF  METHOD.  41 

metrician.  The  second  is,  when  an  equation  is  found, 
to  be  able  to  judge  whether  the  truth  or  falsity  of  the 
question  may  be  deduced  from  it,  or  no ;  which  yet  re- 
quires greater  knowledge.  And  the  third  is,  when 
such  an  equation  is  found,  as  is  fit  for  the  solution  of 
the  question,  to  know  how  to  resolve  the  same  in  such 
manner,  that  the  truth  or  falsity  may  thereby  mani- 
festly appear ;  which,  in  hard  questions,  cannot  be  done 
without  the  knowledge  of  the  nature  of  crooked-lined 
figures ;  but  he  that  understands  readily  the  nature  and 
properties  of  these,  is  a  complete  geometrician.  It 
happens  besides,  that  for  the  finding  out  of  equations, 
there  is  no  certain  method,  but  he  is  best  able  to  do  it, 
that  has  the  best  natural  wit. 


PART  II. 

THE  FIRST    GROUNDS   OF 
PHILOSOPHY. 

CHAPTER  VII.* 

OF  PLACE  AND  TIME. 

I.  Things  that  have  no  existence,  may  nevertheless  be  under- 
stood and  computed. — 2.  What  is  Space. — 3.  Time. — 4.  Part. 
5.  Division. — 6.  One. — 7.  Number. — 8.  Composition. — 
9.  The  whole. — 10.  Spaces  and  times  contiguous,  and  con- 
tinual.— 11  Beginning,  end,  way,  finite,  infinite. — 12.  What 
is  infinite  in  power.  Nothing  infinite  can  be  truly  said  to  be 
either  whole,  or  one ;  nor  infinite  spaces  or  times,  many. — 
13.  Division  proceeds  not  to  the  least. 

I.  In  the  teaching  of  natural  philosophy,  I  cannot 
begin  better  (as  I  have  already  shewn)  than  from 
privation;  that  is,  from  feigning  the  world  to  be  anni- 
hilated. But,  if  such  annihilation  of  all  things  be  sup- 
posed, it  may  perhaps  be  asked,  what  would  remain  for 
any  man  (whom  only  I  except  from  this  universal  anni- 
hilation of  things)  to  consider  as  the  subject  of 
philosophy,  or  at  all  to  reason  upon ;  or  what  to  give 
names  unto  for  ratiocination's  sake. 

I  say,  therefore,  there  would  remain  to  that  man 


*  For   parallel    passages    from    the    Latin   text   of   chapters 
VII.-X.  of  De  Corpore,  cf.  pp.  183  seq. 

43 


44  CONCERNING  BODY. 

ideas  of  the  world,  and  of  all  such  bodies  as  he  had, 
before  their  annihilation,  seen  with  his  eyes,  or  per- 
ceived by  any  other  sense ;  that  is  to  say,  the  memory 
and  imagination  of  magnitudes,  motions,  sounds, 
colours,  &c.  as  also  of  their  order  and  parts.  All 
which  things,  though  they  be  nothing  but  ideas  and 
phantasms,  happening  internally  to  him  that  imagineth  ; 
yet  they  will  appear  as  if  they  were  external,  and  not 
at  all  depending  upon  any  power  of  the  mind.  And 
these  are  the  things  to  which  he  would  give  names, 
and  subtract  them  from,  and  compound  them  with  one 
another.  For  seeing,  that  after  the  destruction  of  all 
other  things,  I  suppose  man  still  remaining,  and  namely 
that  he  thinks,  imagines,  and  remembers,  there  can  be 
nothing  for  him  to  think  of  but  what  is  past ;  nay,  if 
we  do  but  observe  diligently  what  it  is  we  do  when  we 
consider  and  reason,  we  shall  find,  that  though  all 
things  be  still  remaining  in  the  world,  yet  we  compute 
nothing  but  our  own  phantasms.  For  when  we  cal- 
culate the  magnitude  and  motions  of  heaven  or  earth, 
we  do  not  ascend  into  heaven  that  we  may  divide  it 
into  parts,  or  measure  the  motions  thereof,  but  we  do  it 
sitting  still  in  our  closets  or  in  the  dark.  Now  things 
may  be  considered,  that  is,  be  brought  into  account, 
either  as  internal  accidents  of  our  mind,  in  which  man- 
ner we  consider  them  when  the  question  is  about  some 
faculty  of  the  mind;  or  as  species  of  external  things, 
not  as  really  existing,  but  appearing  only  to  exist,  or 
to  have  a  being  without  us.  And  in  this  manner  we 
are  now  to  consider  them. 

2.  If  therefore  we  remember,  or  have  a  phantasm 
of  any  thing  that  was  in  the  world  before  the  supposed 
annihilation  of  the  same ;  and  consider,  not  that  the 
thing  was  such  or  such,  but  only  that  it  had  a  being 


OF  PLACE  AND  TIME.  45 

without  the  mind,  we  have  presently  a  conception  of 
that  we  call  space:  an  imaginary  space  indeed,  because 
a  mere  phantasm,  yet  that  very  thing  which  all  men  call 
so.  For  no  man  calls  it  space  for  being  already  filled, 
but  because  it  may  be  filled;  nor  does  any  man  think 
bodies  carry  their  places  away  with  them,  but  that  the 
same  space  contains  sometimes  one,  sometimes  another 
body;  which  could  not  be  if  space  should  always  ac- 
company the  body  which  is  once  in  it.  And  this  is  of 
itself  so  manifest,  that  I  should  not  think  it  needed  any 
explaining  at  all,  but  that  I  find  space  to  be  falsely 
defined  by  certain  philosophers,  who  infer  from  thence, 
one,  that  the  world  is  infinite  (for  taking  space  to  be 
the  extension  of  bodies,  and  thinking  extension  may 
encrease  continually,  he  infers  that  bodies  may  be  in- 
finitely extended)  ;  and,  another,  from  the  same  defi- 
nition, concludes  rashly,  that  it  is  impossible  even  to 
God  himself  to  create  more  worlds  than  one;  for,  if 
another  world  were  to  be  created,  he  says,  that  seeing 
there  is  nothing  without  this  world,  and  therefore  (ac- 
cording to  his  definition)  no  space,  that  new  wrorld 
must  be  placed  in  nothing ;  but  in  nothing  nothing  can 
be  placed ;  which  he  affirms  only,  without  showing  any 
reason  for  the  same ;  whereas  the  contrary  is  the  truth : 
for  more  cannot  be  put  into  a  place  already  filled,  so 
much  is  empty  space  fitter  than  that,  which  is  full,  for 
the  receiving  of  new  bodies.  Having  therefore  spoken 
thus  much  for  these  men's  sakes,  and  for  theirs  that 
assent  to  them,  I  return  to  my  purpose,  and  define  space 
thus  :  Space  is  the  phantasm  of  a  thing  existing  with- 
out the  mind  simply;  that  is  to  say,  that  phantasm,  in 
which  we  consider  no  other  accident,  but  only  that  it 
appears  without  us. 
3.     As  a  body  leaves  a  phantasm  of  its  magnitude  in 


46  CONCERNING  BODY. 

the  mind,  so  also  a  moved  body  leaves  a  phantasm  of  its 
motion,  namely,  an  idea  of  that  body  passing  out  of  one 
space  into  another  by  continual  succession.  And  this 
idea,  or  phantasm,  is  that,  which  (without  receding 
much  from  the  common  opinion,  or  from  Aristotle's 
definition)  I  call  Time.  For  seeing  all  men  confess  a 
year  to  be  time,  and  yet  do  not  think  a  year  to  be  the 
accident  or  affection  of  any  body,  they  must  needs  con- 
fess it  to  be,  not  in  the  things  without  us,  but  only  in  the 
thought  of  the  mind.  So  when  they  speak  of  the  times 
of  their  predecessors,  they  do  not  think  after  their 
predecessors  are  gone,  that  their  times  can  be  any 
where  else  than  in  the  memory  of  those  that  remember 
them.  And  as  for  those  that  say,  days,  years,  and 
months  are  the  motions  of  the  sun  and  moon,  see- 
ing it  is  all  one  to  say,  motion  past  and  motion  de- 
stroyed, and  that  future  motion  is  the  same  with 
motion  which  is  not  yet  begun,  they  say  that,  which 
they  do  not  mean,  that  there  neither  is,  nor  has  been, 
nor  shall  be  any  time :  for  of  whatsoever  it  may  be  said, 
it  has  been  or  it  shall  be,  of  the  same  also  it  might  have 
been  said  heretofore,  or  may  be  said  hereafter,  it  is. 
What  then  can  days,  months,  and  years,  be,  but  the 
names  of  such  computations  made  in  our  mind  ?  Time 
therefore  is  a  phantasm,  but  a  phantasm  of  motion,  for 
if  we  would  know  by  what  moments  time  passes  away, 
we  make  use  of  some  motion  or  other,  as  of  the  sun,  of 
a  clock,  of  the  sand  in  an  hourglass,  or  we  mark  some 
line  upon  which  we  imagine  something  to  be  moved, 
there  being  no  other  means  by  which  we  can  take 
notice  of  any  time  at  all.  And  yet,  when  I  say  time  is 
a  phantasm  of  motion,  I  do  not  say  this  is  sufficient  to 
define  it  by ;  for  this  word  time  comprehends  the  notion 
of  former  and  latter,  or  of  succession  in  the  motion  of 


OF  PLACE  AND  TIME.  47 

a  body,  in  as  much  as  it  is  first  here  then  there. 
Wherefore  a  complete  definition  of  time  is  such 
as  this,  time  is  the  phantasm  of  before  and  after  in 
motion;  which  agrees  with  this  definition  of  Aristotle, 
time  is  the  number  of  motion  according  to  former  and 
latter;  for  that  numbering  is  an  act  of  the  mind;  and 
therefore  it  is  all  one  to  say,  time  is  the  number  of  mo- 
tion according  to  former  and  latter;  and  time  is  a  phan- 
tasm of  motion  numbered.  But  that  other  definition, 
time  is  the  measure  of  motion,  is  not  so  exact,  for  we 
measure  time  by  motion  and  not  motion  by  time. 

4.  One  space  is  called  part  of  another  space,  and 
one  time  part  of  another  time,  when  this  contains  that 
and  something  besides.  From  whence  it  may  be  col- 
lected, that  nothing  can  rightly  be  called  a  part,  but 
that  which  is  compared  with  something  that  contains  it. 

5.  And  therefore  to  make  parts,  or  to  part  or 
divide  space  or  time,  is  nothing  else  but  to  consider 
one  and  another  within  the  same ;  so  that  if  any  man 
divide  space  or  time,  the  diverse  conceptions  he  has 
are  more,  by  one,  than  the  parts  he  makes ;  for  his  first 
conception  is  of  that  which  is  to  be  divided,  then  of 
some  part  of  it,  and  again  of  some  other  part  of  it,  and 
so  forwards  as  long  as  he  goes  on  in  dividing. 

But  it  is  to  be  noted,  that  here,  by  division,  I  do  not 
mean  the  severing  or  pulling  asunder  of  one  space  or 
time  from  another  (for  does  any  man  think  that  one 
hemisphere  may  be  separated  from  the  other  hemi- 
sphere, or  the  first  hour  from  the  second?)  but  diver- 
sity of  consideration ;  so  that  division  is  not  made  by 
the  operation  of  the  hands  but  of  the  mind. 

6.  When  space  or  time  is  considered  among  other 
spaces  or  times,  it  is  said  to  be  one,  namely,  one  of 
them;  for  except  one  space  might  be  added  to  another, 


48  CONCERNING  BODY. 

and  subtracted  from  another  space,  and  so  of  time,  it 
would  be  sufficient  to  say  space  or  time  simply,  and 
superfluous  to  say  one  space  or  one  time,  if  it  could  not 
be  conceived  that  there  were  another.  The  common 
definition  of  one,  namely,  that  one  is  that  which  is  un- 
divided, is  obnoxious  to  an  absurd  consequence;  for  it 
may  thence  be  inferred,  that  whatsoever  is  divided  is 
many  things,  that  is,  that  every  divided  thing,  is 
divided  things,  which  is  insignificant. 

7.  Number  is  one  and  one,  or  one  one  and  one,  and 
so  forwards;  namely,  one  and  one  make  the  number 
two,  and  one  one  and  one  the  number  three;  so  are  all 
other  numbers  made;  which  is  all  one  as  if  we  should 
say,  number  is  unities. 

8.  To  compound  space  of  spaces,  or  time  of  times, 
is  first  to  consider  them  one  after  another,  and  then 
altogether  as  one ;  as  if  one  should  reckon  first  the 
head,  the  feet,  the  arms,  and  the  body,  severally,  and 
then  for  the  account  of  them  all  together  put  man.  And 
that  which  is  so  put  for  all  the  severals  of  which  it 
consists,  is  called  the  whole  ;  and  those  severals,  when 
by  the  division  of  the  whole  they  come  again  to  be 
considered  singly,  are  parts  thereof;  and  therefore  the 
whole  and  all  the  parts  taken  together  are  the  same 
thing.  And  as  I  noted  above,  that  in  division  it  is  not 
necessary  to  pull  the  parts  asunder ;  so  in  composition, 
it  is  to  be  understood,  that  for  the  making  up  of  a 
whole  there  is  no  need  of  putting  the  parts  together, 
so  as  to  make  them  touch  one  another,  but  only  of  col- 
lecting them  into  one  sum  in  the  mind.  For  thus  all 
men,  being  considered  together,  make  up  the  whole  of 
mankind,  though  never  so  much  dispersed  by  time  and 
place ;  and  twelve  hours,  though  the  hours  of  several 
days,  may  be  compounded  into  one  number  of  twelve. 


OF  PLACE  AND  TIME.  49 

9.  This  being  well  understood,  it  is  manifest  that 
nothing  can  rightly  be  called  a  whole,  that  is  not  con- 
ceived to  be  compounded  of  parts,  and  that  it  may  be 
divided  into  parts ;  so  that  if  we  deny  that  a  thing  has 
parts,  we  deny  the  same  to  be  a  whole.  For  example, 
if  we  say  the  soul  can  have  no  parts,  we  affirm  that  no 
soul  can  be  a  whole  soul.  Also  it  is  manifest,  that 
nothing  has  parts  till  it  be  divided ;  and  when  a  thing 
is  divided,  the  parts  are  only  so  many  as  the  division 
makes  them.  Again,  that  a  part  of  a  part  is  a  part  of 
the  whole;  and  thus  any  part  of  the  number  four,  as 
two,  is  a  part  of  the  number  eight;  for  four  is  made  of 
two  and  two;  but  eight  is  compounded  of  two,  two, 
and  four,  and  therefore  two,  which  is  a  part  of  the 
part  four,  is  also  a  part  of  the  whole  eight. 

10.  Two  spaces  are  said  to  be  contiguous,  when 
there  is  no  other  space  betwixt  them.  But  two  times, 
betwixt  which  there  is  no  other  time,  are  called  imme- 
diate, as  A  B,  B  C.  And  any  two  a  -a  r 
spaces,  as  well  as  times,  are  said     


to  be  continual,  when  they  have  one  common  part, 
as  A  C,  B  D,  where  the  part  BC    ^        -q        q       D 

is  common;  and  more  spaces  and 

times  are  continual,  when  every  two  which  are  next 
one  another  are  continual. 

11.  That  part  which  is  between  two  other  parts,  is 
called  a  mean  ;  and  that  which  is  not  between  two 
other  parts,  an  extreme.  And  of  extremes,  that  which 
is  first  recokned  is  the  bfginning,  and  that  which  last, 
the  end  ;  and  all  the  means  together  taken  are  the  way. 
Also,  extreme  parts  and  limits  are  the  same  thing.  And 
from  hence  it  is  manifest,  that  beginning  and  end  de- 
pend upon  the  order  in  which  we  number  them;  and 
that  to  terminate  or  limit  space  and  time,  is  the  same 


50  CONCERNING  BODY. 

thing  with  imagining  their  beginning  and  end;  as  also 
that  every  thing  is  finite  or  infinite,  according  as 
we  imagine  or  not  imagine  it  limited  or  terminated 
every  way ;  and  that  the  limits  of  any  number  are 
unities,  and  of  these,  that  which  is  the  first  in  our  num- 
bering is  the  beginning,  and  that  which  we  number 
last,  is  the  end.  When  we  say  number  is  infinite,  we 
mean  only  that  no  number  is  expressed;  for  when  we 
speak  of  the  numbers  two,  three,  a  thousand,  &c.  they 
are  always  Unite.  But  when  no  more  is  said  but  this, 
number  is  infinite,  it  is  to  be  understood  as  if  it  were 
said,  this  name  number  is  an  indefinite  name. 

12.  Space  or  time  is  said  to  be  finite  in  power,  or 
terminable,  when  there  may  be  assigned  a  number  of 
finite  spaces  or  times,  as  of  paces  or  hours,  than  which 
there  can  be  no  greater  number  of  the  same  measure 
in  that  space  or  time ;  and  infinite  in  power  is  that 
space  or  time,  in  which  a  greater  number  of  the  said 
paces  or  hours  may  be  assigned,  than  any  number  that 
can  be  given.  But  we  must  note,  that,  although  in  that 
space  or  time  which  is  infinite  in  power,  there  may  be 
numbered  more  paces  or  hours  than  any  number  that 
can  be  assigned,  yet  their  number  will  always  be  finite ; 
for  every  number  is  finite.  And  therefore  his  ratio- 
cination was  not  good,  that  undertaking  to  prove  the 
world  to  be  finite,  reasoned  thus :  //  the  world 
be  infinite,  then  there  may  be  taken  in  it  some  part 
which  is  distant  from  us  an  infinite  number  of  paces: 
but  no  such  part  can  be  taken;  wherefore  the  world  is 
not  infinite;  because  that  consequence  of  the  major 
proposition  is  false ;  for  in  an  infinite  space,  whatsoever 
we  take  or  design  in  our  mind,  the  distance  of  the  same 
from  us  is  a  finite  space;  for  in  the  very  designing  of 
the  place  thereof,  we  put  an  end  to  that  space,  of  which 


OF  PLACE  AND  TIME.  51 

we  ourselves  are  the  beginning;  and  whatsoever  any 
man  with  his  mind  cuts  off  both  ways  from  infinite,  he 
determines  the  same,  that  is,  he  makes  it  finite. 

Of  infinite  space  or  time,  it  cannot  be  said  that  it  is 
a  whole  or  one:  not  a  whole,  because  not  compounded 
of  parts;  for  seeing  parts,  how  many  soever  they  be, 
are  severally  finite,  they  will  also,  when  they  are  all 
put  together,  make  a  whole  finite:  nor  one,  because 
nothing  can  be  said  to  be  one,  except  there  be  another 
to  compare  it  with;  but  it  cannot  be  conceived  that 
there  are  two  spaces,  or  two  times,  infinite.  Lastly, 
when  we  make  question  whether  the  world  be  finite  or 
infinite,  we  have  nothing  in  our  mind  answering  to  the 
name  world;  for  whatsoever  we  imagine,  is  therefore 
finite,  though  our  computation  reach  the  fixed  stars,  or 
the  ninth  or  tenth,  nay,  the  thousandth  sphere.  The 
meaning  of  the  question  is  this  only,  whether  God  has 
actually  made  so  great  an  addition  of  body  to  body,  as 
we  are  able  to  make  of  space  to  space. 

13.  And,  therefore,  that  which  is  commonly  said, 
that  space  and  time  may  be  divided  infinitely,  is  not  to 
be  so  understood,  as  if  there  might  be  any  infinite  or 
eternal  division ;  but  rather  to  be  taken  in  this  sense, 
whatsoever  is  divided,  is  divided  into  such  parts  as  may 
again  be  divided;  or  thus,  the  least  divisible  thing  is  not 
to  be  given;  or,  as  geometricians  have  it,  no  quantity  is 
so  small,  but  a  less  may  be  taken;  which  may  easily  be 
demonstrated  in  this  manner.  Let  any  space  or  time, 
that  which  was  thought  to  be  the  least  divisible,  be 
divided  into  two  equal  parts,  A  and  B.  I  say  either 
of  them,  as  A,  may  be  divided  again.  For  suppose 
the  part  A  to  be  contiguous  to  the  part  B  of  one  side, 
and  of  the  other  side  to  some  other  space  equal  to  B. 
This  whole  space,  therefore,  being  greater  than  the 


52  CONCERNING  BODY. 

space  given,  is  divisible.  Wherefore,  if  it  be  divided 
into  two  equal  parts,  the  part  in  the  middle,  which  is  A, 
will  be  also  divided  into  two  equal  parts;  and  there- 
fore A  was  divisible. 

CHAPTER  VIII. 

OF  BODY  AND  ACCIDENT. 

I.  Body  defined. — 2.  Accident  denned. — 3.  How  an  accident 
may  be  understood  to  be  in  its  subject. — 4.  Magnitude,  what 
it  is. — 5.  Place,  what  it  is,  and  that  it  is  immovable. — 6. 
What  is  full  and  empty. — 7.  Here,  there,  somewhere,  what 
they  signify. — 8.  Many  bodies  cannot  be  in  one  place,  nor 
one  body  in  many  places. — 9.  Contiguous  and  continual,  what 
they  are. — 10.  The  definition  of  motion.  No  motion  intelli- 
gible but  with  time. — 11.  What  it  is  to  be  at  rest,  to  have 
been  moved,  and  to  be  moved.  No  motion  to  be  conceived, 
without  the  conception  of  past  and  future. — 12.  A  point,  a 
line,  superfices  and  solid,  what  they  are. — 13.  Equal,  greater, 
and  less  in  bodies  and  magnitudes,  what  they  are. — 14.  One 
and  the  same  body  has  always  one  and  the  same  magnitude. 
15.  Velocity,  what  it  is. — 16.  Equal,  greater,  and  less  in 
times,  what  they  are. — 17.  Equal,  greater,  and  less,  in  veloc- 
ity, what. — 18.  Equal,  greater,  and  less,  in  motion,  what. — 
19.  That  which  is  at  rest,  will  always  be  at  rest,  except  it  be 
moved  by  some  external  thing;  and  that  which  is  moved, 
will  always  be  moved,  unless  it  be  hindered  by  some  exter- 
nal thing. — 20.  Accidents  are  generated  and  destroyed,  but 
bodies  not  so. — 21.  An  accident  cannot  depart  from  its  sub- 
ject.— 22.  Nor  be  moved. — 23.  Essence,  form,  and  matter, 
what  they  are. — 24.  First  matter,  what.— 25.  That  the  whole 
is  greater  than  any  part  thereof,  why  demonstrated. 

i.  Having  understood  what  imaginary  space  is,  in 
which  we  supposed  nothing  remaining  without  us,  but 
all  those  things  to  be  destroyed,  that,  by  existing  here- 
tofore, left  images  of  themselves  in  our  minds;  let  us 


OF  BODY  AND  ACCIDENT.  53 

now  suppose  some  one  of  those  things  to  be  placed 
again  in  the  world,  or  created  anew.  It  is  necessary, 
therefore,  that  this  new-created  or  replaced  thing  do 
not  only  fill  some  part  of  the  space  above  mentioned, 
or  be  coincident  and  coextended  with  it,  but  also  that 
it  have  no  dependance  upon  our  thought.  And  this  is 
that  which,  for  the  extension  of  it,  we  commonly  call 
body;  and  because  it  depends  not  upon  our  thought, 
we  say  is  a  thing  subsisting  of  itself;  as  also  existing, 
because  without  us ;  and,  lastly,  it  is  called  the  subject, 
because  it  is  so  placed  in  and  subjected  to  imaginary 
space,  that  it  may  be  understood  by  reason,  as  well  as 
perceived  by  sense.  The  definition,  therefore,  of  body 
may  be  this,  a  body  is  that,  which  having  no  depend- 
ance upon  our  thought,  is  coincident  or  coextended 
with  some  part  of  space. 

2.  But  what  an  accident  is  cannot  so  easily  be  ex- 
plained by  any  definition,  as  by  examples.  Let  us  im- 
agine, therefore,  that  a  body  fills  any  space,  or  is 
coextended  with  it;  that  coextension  is  not  the  coex- 
tended body:  and,  in  like  manner,  let  us  imagine  that 
the  same  body  is  removed  out  of  its  place ;  that  re- 
moving is  not  the  removed  body:  or  let  us  think  the 
same  not  removed;  that  not  removing  or  rest  is  not 
the  resting  body.  What,  then,  are  these  things  ?  They 
are  accidents  of  that  body.  But  the  thing  in  question 
is,  what  is  an  accident ?  which  is  an  enquiry  after  that 
which  we  know  already,  and  not  that  which  we  should 
enquire  after.  For  who  does  not  always  and  in  the 
same  manner  understand  him  that  says  any  thing  is 
extended,  or  moved,  or  not  moved?  But  most  men 
will  have  it  be  said  that  an  accident  is  something, 
namely,  some  part  of  a  natural  thing,  when,  indeed, 
it  is  no  part  of  the  same.     To  satisfy  these  men,  as 


54  CONCERNING  BODY. 

well  as  may  be,  they  answer  best  that  define  an  acci- 
dent to  be  the  manner  by  which  any  body  is  con- 
ceived; which  is  all  one  as  if  they  should  say,  an  ac- 
cident is  that  faculty  of  any  body,  by  which  it  works 
in  us  a  conception  of  itself.  Which  definition,  though 
it  be  not  an  answer  to  the  question  propounded,  yet 
it  is  an  answer  to  that  question  which  should  have  been 
propounded,  namely,  whence  does  it  happen  that  one 
part  of  any  body  appears  here,  another  there?  For 
this  is  well  answered  thus:  it  happens  from  the  ex- 
tension of  that  body.  Or,  how  comes  it  to  pass  that 
the  whole  body,  by  succession,  is  seen  now  here,  now 
there?  and  the  answer  will  be,  by  reason  of  its  mo- 
tion. Or,  lastly,  whence  is  it  that  any  body  possesseth 
the  same  space  for  sometime?  and  the  answer  will 
be,  because  it  is  not  moved.  For  if  concerning  the 
name  of  a  body,  that  is,  concerning  a  concrete  name, 
it  be  asked,  what  is  it?  the  answer  must  be  made  by 
definition;  for  the  question  is  concerning  the  sig- 
nification of  the  name.  But  if  it  be  asked  concerning 
an  abstract  name,  what  is  it?  the  cause  is  demanded 
why  a  thing  appears  so  or  so.  As  if  it  be  asked,  what 
is  hard?  The  answer  will  be,  hard  is  that,  whereof  no 
part  gives  place,  but  when  the  whole  gives  place.  But 
if  it  be  demanded,  what  is  hardness?  a  cause  must  be 
shewn  why  a  part  does  not  give  place,  except  the  whole 
give  place.  Wherefore,  I  define  an  accident  to  be  the 
manner  of  our  conception  of  body. 

3.  When  an  accident  is  said  to  be  in  a  body,  it  is 
not  so  to  be  understood,  as  if  any  thing  were  con- 
tained in  that  body;  as  if,  for  example,  redness  were 
in  blood,  in  the  same  manner,  as  blood  is  in  a  bloody 
cloth,  that  is,  as  a  part  in  the  whole;  for  so,  an  acci- 
dent would  be  a  body  also.     But,  as  magnitude,  or 


OF  BODY  AND  ACCIDENT.  55 

rest,  or  motion,  is  in  that  which  is  great,  or  which 
resteth,  or  which  is  moved,  (which,  how  it  is  to  be 
understood,  every  man  understands)  so  also  it  is  to  be 
understood,  that  every  other  accident  is  in  its  subject. 
And  this,  also  is  explicated  by  Aristotle  no  other- 
wise than  negatively,  namely,  that  an  accident  is  in  its 
subject,  not  as  any  part  thereof,  but  so  as  that  it  may  be 
away,  the  subject  still  remaining;  which  is  right,  sav- 
ing that  there  are  certain  accidents  which  can  never 
perish  except  the  body  perish  also;  for  no  body  can 
be  conceived  to  be  without  extension,  or  without 
figure.  All  other  accidents,  which  are  not  common 
to  all  bodies,  but  peculiar  to  some  only,  as  to  be  at 
rest,  to  be  moved,  colour,  hardness,  and  the  like,  do 
perish  continually,  and  are  succeeded  by  others;  yet 
so,  as  that  the  body  never  perisheth.  And  as  for  the 
opinion  that  some  may  have,  that  all  other  accidents 
are  not  in  their  bodies  in  the  same  manner  that  ex- 
tension, motion,  rest,  or  figure,  are  in  the  same;  for 
example,  that  colour,  heat,  odour,  virtue,  vice,  and  the 
like,  are  otherwise  in  them,  and,  as  they  say,  inherent; 
I  desire  they  would  suspend  their  judgment  for  the 
present,  and  expect  a  little,  till  it  be  found  out  by  ratio- 
cination, whether  these  very  accidents  are  not  also  cer- 
tain motions  either  of  the  mind  of  the  perceiver,  or  of 
the  bodies  themselves  which  are  perceived ;  for  in  the 
search  of  this,  a  great  part  of  natural  philosophy  con- 
sists. 

4.  The  extension  of  a  body,  is  the  same  thing  with 
the  magnitude  of  it,  or  that  which  some  call  real  space. 
But  this  magnitude  does  not  depend  upon  our  cogita- 
tion, as  imaginary  space  doth;  for  this  is  an  effect  of 
our   imagination,  but  magnitude  is  the  cause  of  it; 


56  CONCERNING  BODY. 

this  is  an  accident  of  the  mind,  that  of  a  body  existing 
out  of  the  mind. 

5.  That  space,  by  which  word  I  here  understand 
imaginary  space,  which  is  coincident  with  the  magni- 
tude of  any  body,  is  called  the  place  of  that  body; 
and  the  body  itself  is  that  which  we  call  the  thing 
placed.  Now  place,  and  the  magnitude  of  the  thing 
placed,  differ.  First  in  this,  that  a  body  keeps  always 
the  same  magnitude,  both  when  it  is  at  rest,  and  when 
it  is  moved;  but  when  it  is  moved,  it  does  not  keep 
the  same  place.  Secondly  in  this,  that  place  is  a  phan- 
tasm of  any  body  of  such  and  such  quantity  and  figure ; 
but  magnitude  is  the  peculiar  accident  of  every  body; 
for  one  body  may  at  several  times  have  several  places, 
but  has  always  one  and  the  same  magnitude.  Thirdly 
in  this,  that  place  is  nothing  out  of  the  mind,  nor 
magnitude  any  thing  within  it.  And  lastly,  place  is 
feigned  extension,  but  magnitude  true  extension;  and 
a  placed  body  is  not  extension,  but  a  thing  extended. 
Besides,  place  is  immovable;  for,  seeing  that  which  is 
moved,  is  understood  to  be  carried  from  place  to  place, 
if  place  were  moved,  it  would  also  be  carried  from 
place  to  place,  so  that  one  place  must  have  another 
place,  and  that  place  another  place,  and  so  on  infinitely, 
which  is  ridiculous.  And  as  for  those,  that,  by 
making  place  to  be  of  the  same  nature  with  real  space, 
would  from  thence  maintain  it  to  be  immovable,  they 
also  make  place,  though  they  do  not  perceive  they  make 
it  so,  to  be  a  mere  phantasm.  For  whilst  one  affirms 
that  place  is  therefore  said  to  be  immovable,  because 
space  in  general  is  considered  there ;  if  he  had  remem- 
bered that  nothing  is  general  or  universal  besides 
names  or  signs,  he  would  easily  have  seen  that  that 
space,  which  he  says  is  considered  in  general,  is  noth- 


OF  BODY  AND  ACCIDENT.  57 

ing  but  a  phantasm,  in  the  mind  or  the  memory,  of  a 
body  of  such  magnitude  and  such  figure.  And  whilst 
another  says :  real  space  is  made  immovable  by  the 
understanding;  as  when,  under  the  superficies  of  run- 
ning water,  we  imagine  other  and  other  water  to  come 
by  continual  succession,  that  superficies  fixed  there 
by  the  understanding,  is  the  immovable  place  of  the 
river :  what  else  does  he  make  it  to  be  but  a  phantasm, 
though  he  do  it  obscurely  and  in  perplexed  words? 
Lastly,  the  nature  of  place  does  not  consist  in  the 
superficies  of  the  ambient,  but  in  solid  space;  for  the 
whole  placed  body  is  coextended  with  its  whole  place, 
and  every  part  of  it  with  every  answering  part  of  the 
same  place ;  but  seeing  every  placed  body  is  a  solid 
thing,  it  cannot  be  understood  to  be  coextended  with 
superficies.  Besides,  how  can  any  whole  body  be 
moved,  unless  all  its  parts  be  moved  together  with 
it?  Or  how  can  the  internal  parts  of  it  be  moved, 
but  by  leaving  their  place  ?  But  the  internal  parts  of  a 
body  cannot  leave  the  superficies  of  an  external  part 
contiguous  to  it ;  and,  therefore,  it  follows,  that  if 
place  be  the  superficies  of  the  ambient,  then  the  parts 
of  a  body  moved,  that  is,  bodies  moved,  are  not 
moved. 

6.  Space,  or  place,  that  is  possessed  by  a  body,  is 
called  full,  and  that  which  is  not  so  possessed,  is  called 
empty. 

J.  Here,  there,  in  the  country,  in  the  city,  and 
other  the  like  names,  by  which  answer  is  made  to  the 
question  where  is  it?  are  not  properly  names  of  place, 
nor  do  they  of  themselves  bring  into  the  mind  the  place 
that  is  sought;  for  here  and  there  signify  nothing,  un- 
less the  thing  be  shewn  at  the  same  time  with  the 
finger  or  something  else ;  but  when  the  eye  of  him 


58  CONCERNING  BODY. 

that  seeks,  is,  by  pointing  or  some  other  sign,  directed 
to  the  thing  sought,  the  place  of  it  is  not  hereby  de- 
fined by  him  that  answers,  but  found  out  by  him  that 
asks  the  question.  Now  such  shewings  as  are  made 
by  words  only,  as  when  we  say,  in  the  country,  or  in 
the  city,  are  some  of  greater  latitude  than  others,  as 
when  we  say,  in  the  country,  in  the  city,  in  such  a 
street,  in  a  house,  in  the  chamber,  in  bed,  &c.  For 
these  do,  by  little  and  little,  direct  the  seeker  nearer 
to  the  proper  place;  and  yet  they  do  not  determine 
the  same,  but  only  restrain  it  to  a  lesser  space,  and 
signify  no  more,  than  that  the  place  of  the  thing  is 
within  a  certain  space  designed  by  those  words,  as  a 
part  is  in  the  whole.  And  all  such  names,  by  which 
answer  is  made  to  the  question  where t  have,  for  their 
highest  genus,  the  name  somewhere.  From  whence  it 
may  be  understood,  that  whatsoever  is  somewhere,  is 
in  some  place  properly  so  called,  which  place  is  part  of 
that  greater  space  that  is  signified  by  some  of  these 
names,  in  the  country,  in  the  city,  or  the  like. 

8.  A  body,  and  the  magnitude,  and  the  place  there- 
of, are  divided  by  one  and  the  same  act  of  the  mind; 
for,  to  divide  an  extended  body,  and  the  extension 
thereof,  and  the  idea  of  that  extension,  which  is  place, 
is  the  same  with  dividing  any  one  of  them;  because 
they  are  coincident,  and  it  cannot  be  done  but  by  mind, 
that  is  by  the  division  of  space.  From  whence  it  is 
manifest,  that  neither  two  bodies  can  be  together  in 
the  same  place,  nor  one  body  be  in  two  places  at  the 
same  time.  Not  two  bodies  in  the  same  place ;  because 
when  a  body  that  fills  its  whole  place  is  divided  into 
two,  the  place  itself  is  divided  into  two  also,  so  that 
there  will  be  two  places.  Not  one  body  in  two  places ; 
for  the  place  that  a  body  fills  being  divided  into  two, 


OF  BODY  AND  ACCIDENT.  59 

the  placed  body  will  be  also  divided  into  two ;  for,  as 
I  said,  a  place  and  the  body  that  fills  that  place,  are 
divided  both  together ;  and  so  there  will  be  two  bodies. 

9.  Two  bodies  are  said  to  be  contiguous  to  one 
another,  and  continual,  in  the  same  manner  as  spaces 
are ;  namely,  those  are  contiguous,  betzveen  which  there 
is  no  space.  Now,  by  space  I  understand,  here  as 
formerly,  an  idea  or  phantasm  of  a  body.  Wherefore, 
though  between  two  bodies  there  be  put  no  other  body, 
and  consequently  no  magnitude,  or,  as  they  call  it,  real 
space,  yet  if  another  body  may  be  put  between  them, 
that  is,  if  there  intercede  any  imagined  space  which 
may  receive  another  body,  then  those  bodies  are  not 
contiguous.  And  this  is  so  easy  to  be  understood,  that 
I  should  wonder  at  some  men,  who  being  otherwise 
skilful  enough  in  philosophy,  are  of  a  different  opin- 
ion, but  that  I  find  that  most  of  those  that  affect  meta- 
physical subtleties  wander  from  truth,  as  if  they  were 
led  out  of  their  way  by  an  ignis  fatuus.  For  can  any 
man  that  has  his  natural  senses,  think  that  two  bodies 
must  therefore  necessarily  touch  one  another,  because 
no  other  body  is  between  them?  Or  that  there  can  be 
no  vacuum,  because  vacuum  is  nothing,  or  as  they  call 
it,  non  ens?  Which  is  as  childish,  as  if  one  should 
reason  thus ;  no  man  can  fast,  because  to  fast  is  to 
eat  nothing;  but  nothing  cannot  be  eaten.  Continual, 
are  any  two  bodies  that  have  a  common  part;  and 
more  than  tzvo  are  continual,  when  every  two,  that 
are  next  to  one  another,  are  continual. 

10.  Motion  is  a  continual  relinquishing  of  one 
place,  and  acquiring  of  another;  and  that  place  which 
is  relinquished  is  commonly  called  the  terminus  a  quo, 
as  that  which  is  acquired  is  called  the  terminus  ad 
quern;  I  say  a  continual  relinquishing,  because  no  body, 


60  CONCERNING  BODY. 

how  little  soever,  can  totally  and  at  once  go  out  of  its 
former  place  into  another,  so,  but  that  some  part  of 
it  will  be  in  a  part  of  a  place  which  is  common  to  both, 
namely,  to  the  relinquished  and  the  acquired  places. 
A  G  B  I  E  For  example,  let  any  body  be  in  the 
place  A  C  B  D;  the  same  body  can- 
not come  into  the  place  B  D  E  F, 
_  but  it  must  first  be   in   G  H   I   K, 


f  H  D    K    F 

v^  ix  u    xv    r  wj10se  part  G  H  B  D  is  common  to 

both  the  places  A  C  B  D,  and  G  H  I  K,  and  whose  part 
B  D  I  K,  is  common  to  both  the  places  G  H  I  K,  and 
B  D  E  F.  Now  it  cannot  be  conceived  that  anything 
can  be  moved  without  time ;  for  time  is,  by  the  defini- 
tion of  it,  a  phantasm,  that  is,  a  conception  of  motion ; 
and,  therefore,  to  conceive  that  any  thing  may  be 
moved  without  time,  were  to  conceive  motion  without 
motion,  which  is  impossible. 

ii.  That  is  said  to  be  at  rest,  which,  during  any 
time,  is  in  one  place;  and  that  to  be  moved,  or  to  have 
been  moved,  which,  whether  it  be  now  at  rest  or  moved, 
zvas  formerly  in  another  place  than  that  which  it  is  now 
in.  From  which  definitions  it  may  be  inferred,  first, 
that  whatsoever  is  moved,  has  been  moved;  for  if  it  be 
still  in  the  same  place  in  which  it  was  formerly,  it  is  at 
rest,  that  is,  it  is  not  moved,  by  the  definition  of  rest; 
but  if  it  be  in  another  place,  it  has  been  moved,  by  the 
definition  of  moved.  Secondly,  that  what  is  moved, 
will  yet  be  moved;  for  that  which  is  moved,  leaveth  the 
place  where  it  is,  and  therefore  will  be  in  another 
place,  and  consequently  will  be  moved  still.  Thirdly, 
that  whatsoever  is  moved,  is  not  in  one  place  during 
any  time,  hozv  little  soever  that  time  be;  for  by  the 
definition  of  rest,  that  which  is  in  one  place  during  any 
time,  is  at  rest. 


OF  BODY  AND  ACCIDENT.  61 

There  is  a  certain  sophism  against  motion,  which 
seems  to  spring  from  the  not  understanding  of  this 
last  proposition.  For  they  say,  that,  if  any  body  be 
moved,  it  is  moved  either  in  the  place  where  it  is,  or  in 
the  place  where  it  is  not;  both  which  are  false;  and 
therefore  nothing  is  moved.  But  the  falsity  lies  in  the 
major  proposition;  for  that  which  is  moved,  is  neither 
moved  in  the  place  where  it  is,  nor  in  the  place  where 
it  is  not;  but  from  the  place  where  it  is,  to  the  place 
where  it  is  not.  Indeed  it  cannot  be  denied  but  that 
whatsoever  is  moved,  is  moved  somewhere,  that  is, 
within  some  space;  but  then  the  place  of  that  body  is 
not  that  whole  space,  but  a  part  of  it,  as  is  said  above 
in  the  seventh  article.  From  what  is  above  demon- 
strated, namely,  that  whatsoever  is  moved,  has  also 
been  moved,  and  will  be  moved,  this  also  may  be  col- 
lected, that  there  can  be  no  conception  of  motion,  with- 
out conceiving  past  and  future  time. 

12.  Though  there  be  no  body  which  has  not  some 
magnitude,  yet  if,  when  any  body  is  moved,  the  magni- 
tude of  it  be  not  at  all  considered,  the  way  it  makes  is 
called  a  line,  or  one  single  dimension ;  and  the  space, 
through  which  it  passeth,  is  called  length;  and  the 
body  itself,  a  point;  in  which  sense  the  earth  is  called 
a  point,  and  the  way  of  its  yearly  revolution,  the 
ecliptic  line.  But  if  a  body,  which  is  moved,  be  consid- 
ered as  long,  and  be  supposed  to  be  so  moved,  as  that 
all  the  several  parts  of  it  be  understood  to  make  several 
lines,  then  the  way  of  every  part  of  that  body  is  called 
breadth,  and  the  space  which  is  made  is  called  super- 
ficies, consisting  of  two  dimensions,  one  whereof  to 
every  several  part  of  the  other  is  applied  whole. 
Again,  if  a  body  be  considered  as  having  superficies, 
and  be  understood  to  be  so  moved,  that  all  the  several 


62  CONCERNING  BODY. 

parts  of  it  describe  several  lines,  then  the  way  of  every 
part  of  that  body  is  called  thickness  or  depth,  and  the 
space  which  is  made  is  called  solid,  consisting  of  three 
dimensions,  any  two  whereof  are  applied  whole  to  every 
several  part  of  the  third. 

But  if  a  body  be  considered  as  solid,  then  it  is  not 
possible  that  all  the  several  parts  of  it  should  describe 
several  lines;  for  what  way  soever  it  be  moved,  the 
way  of  the  following  part  will  fall  into  the  way  of  the 
part  before  it,  so  that  the  same  solid  will  still  be  made 
which  the  foremost  superficies  would  have  made  by 
itself.  And  therefore  there  can  be  no  other  dimension 
in  any  body,  as  it  is  a  body,  than  the  three  which  I 
have  now  described;  though,  as  it  shall  be  shewed 
hereafter,  velocity,  which  is  motion  according  to  length, 
may,  by  being  applied  to  all  the  parts  of  a  solid,  make 
a  magnitude  of  motion,  consisting  of  four  dimensions ; 
as  the  goodness  of  gold,  computed  in  all  the  parts  of  it, 
makes  the  price  and  value  thereof. 

13.  Bodies,  how  many  soever  they  be,  that  can 
fill  every  one  the  place  of  every  one,  are  said  to  be 
equal  every  one  to  every  other.  Now,  one  body  may 
fill  the  same  place  which  another  body  filleth,  though 
it  be  not  of  the  same  figure  with  that  other  body,  if  so 
be  that  it  may  be  understood  to  be  reducible  to  the 
same  figure,  either  by  flexion  or  transposition  of  the 
parts.  And  one  body  is  greater  than  another  body, 
when  a  part  of  that  is  equal  to  all  this;  and  less,  when 
all  that  is  equal  to  a  part  of  this.  Also,  magnitudes  are 
equal,  or  greater,  or  lesser,  than  one  another,  for  the 
same  consideration,  namely,  when  the  bodies,  of  which 
they  are  the  magnitudes,  are  either  equal,  or  greater, 
or  less ,  &c. 

14.  One  and  the  same  body  is  always  of  one  and 


OF  BODY  AND  ACCIDENT.  63 

the  same  magnitude.  For  seeing  a  body  and  the  mag- 
nitude and  place  thereof  cannot  be  comprehended  in 
the  mind  otherwise  than  as  they  are  coincident,  if  any 
body  be  understood  to  be  at  rest,  that  is,  to  remain 
in  the  same  place  during  some  time,  and  the  magnitude 
thereof  be  in  one  part  of  that  time  greater,  and  in 
another  part  less,  that  body's  place,  which  is  one  and 
the  same,  will  be  coincident  sometimes  with  greater, 
sometimes  with  less  magnitude,  that  is,  the  same  place 
will  be  greater  and  less  than  itself,  which  is  impossible. 
But  there  would  be  no  need  at  all  of  demonstrating  a 
thing  that  is  in  itself  so  manifest,  if  there  were  not 
some,  whose  opinion  concerning  bodies  and  their  mag- 
nitudes is,  that  a  body  may  exist  separated  from  its 
magnitude,  and  have  greater  or  less  magnitude  be- 
stowed upon  it,  making  use  of  this  principle  for  the 
explication  of  the  nature  of  varum  and  densum. 

15.  Motion,  in  as  much  as  a  certain  length  may  in 
a  certain  time  be  transmitted  by  it,  is  called  velocity 
or  szviftness:  &c.  For  though  swift  be  very  often 
understood  with  relation  to  slower  or  less  swift,  as 
great  is  in  respect  of  less,  yet  nevertheless,  as  magni- 
tude is  by  philosophers  taken  absolutely  for  extension, 
so  also  velocity  or  szviftness  may  be  put  absolutely  for 
motion  according  to  length. 

16.  Many  motions  are  said  to  be  made  in  equal 
times,  when  every  one  of  them  begins  and  ends  to- 
gether with  some  other  motion,  or  if  it  had  begun 
together,  would  also  have  ended  together  with  the 
same.  For  time,  which  is  a  phantasm  of  motion,  can- 
not be  reckoned  but  by  some  exposed  motion ;  as  in 
dials  by  the  motion  of  the  sun  or  of  the  hand;  and  if 
two  or  more  motions  begin  and  end  with  this  motion, 
they  are  said  to  be  made  in  equal  times ;  from  whence 


64  CONCERNING  BODY. 

also  it  is  easy  to  understand  what  it  is  to  be  moved  in 
greater  or  longer  time,  and  in  less  time  or  not  so  long ; 
namely,  that  that  is  longer  moved,  which  beginning 
with  another,  ends  later;  or  ending  together,  began 
sooner. 

17.  Motions  are  said  to  be  equally  swift,  when 
equal  lengths  are  transmitted  in  equal  times;  and 
greater  swiftness  is  that,  wherein  greater  length  is 
passed  in  equal  time,  or  equal  length  in  less  time.  Also 
that  swiftness  by  which  equal  lengths  are  passed  in 
equal  parts  of  time,  is  called  uniform  swiftness  or 
motion ;  and  of  motions  not  uniform,  such  as  become 
swifter  or  slower  by  equal  increasings  or  decreasings 
in  equal  parts  of  time,  are  said  to  be  accelerated  or  re- 
tarded uniformly. 

18.  But  motion  is  said  to  be  greater,  less,  and  equal, 
not  only  in  regard  of  the  length  which  is  transmitted 
in  a  certain  time,  that  is,  in  regard  of  swiftness  only, 
but  of  swiftness  applied  to  every  smallest  particle  of 
magnitude;  for  when  any  body  is  moved,  every  part  of 
it  is  also  moved ;  and  supposing  the  parts  to  be  halves, 
the  motions  of  those  halves  have  their  swiftness  equal 
to  one  another,  and  severally  equal  to  that  of  the  whole  ; 
but  the  motion  of  the  whole  is  equal  to  those  two 
motions,  either  of  which  is  of  equal  swiftness  with  it ; 
and  therefore  it  is  one  thing  for  two  motions  to  be 
equal  to  one  another,  and  another  thing  for  them  to 
be  equally  swift.  And  this  is  manifest  in  two  horses 
that  draw  abreast,  where  the  motion  of  both  the  horses 
together  is  of  equal  swiftness  with  the  motion  of  either 
of  them  singly ;  but  the  motion  of  both  is  greater  than 
the  motion  of  one  of  them,  namely,  double.  Wherefore 
motions  are  said  to  be  simply  equal  to  one  another, 
when  the  swiftness  of  one,  computed  in  every  part  of 


OF  BODY  AND  ACCIDENT.  65 

its  magnitude,  is  equal  to  the  swiftness  of  the  other 
computed  also  in  every  part  of  its  magnitude:  and 
greater  than  one  another,  when  the  swiftness  of  one 
computed  as  above,  is  greater  than  the  szviftness  of  the 
other  so  computed;  and  less,  when  less.  Besides,  the 
magnitude  of  motion  computed  in  this  manner  is  that 
which  is  commonly  called  force. 

19.  Whatsoever  is  at  rest,  will  always  be  at  rest, 
unless  there  be  some  other  body  besides  it,  which,  by 
endeavoring  to  get  into  its  place  by  motion,  suffers  it 
no  longer  to  remain  at  rest.  For  suppose  that  some 
finite  body  exist  and  be  at  rest,  and  that  all  space 
besides  be  empty ;  if  now  this  body  begin  to  be  moved, 
it  will  certainly  be  moved  some  way ;  seeing  therefore 
there  was  nothing  in  that  body  which  did  not  dispose 
it  to  rest,  the  reason  why  it  is  moved  this  way  is  in 
something  out  of  it ;  and  in  like  manner,  if  it  had  been 
moved  any  other  way,  the  reason  of  motion  that  way 
had  also  been  in  something  out  of  it ;  but  seeing  it  was 
supposed  that  nothing  is  out  of  it,  the  reason  of  its 
motion  one  way  would  be  the  same  with  the  reason  of 
its  motion  every  other  way,  wherefore  it  would  be 
moved  alike  all  ways  at  once ;  which  is  impossible. 

In  like  manner,  whatsoever  is  moved,  will  always  be 
moved,  except  there  be  some  other  body  besides  it, 
which  causeth  it  to  rest.  For  if  we  suppose  nothing  to 
be  without  it,  there  will  be  no  reason  why  it  should 
rest  now,  rather  than  at  another  time;  wherefore  its 
motion  would  cease  in  every  particle  of  time  alike; 
which  is  not  intelligible. 

20.  When  we  say  a  living  creature,  a  tree,  or  any 
other  specified  body  is  generated  or  destroyed,  it  is  not 
to  be  so  understood  as  if  there  were  made  a  body  of 
that  which  is  not-body,  or  not  a  body  of  a  body,  but  of  a 


66  CONCERNING  BODY. 

living  creature  not  a  living  creature,  of  a  tree  not  a 
tree,  &c.   that  is,  that  those  accidents  for  which  we  call 
one  thing  a  living  creature,  another  thing  a  tree,  and 
another  by  some  other  name,  are  generated  and  de- 
stroyed ;  and  that  therefore  the  same  names  are  not  to 
be  given  to  them  now,  which  were  given  them  before. 
But  that  magnitude  for  which  we  give  to  any  thing 
the  name  of  body  is  neither  generated  nor  destroyed. 
For  though  we  may  feign  in  our  mind  that  a  point 
may  swell  to  a  huge  bulk,  and  that  this  may  again  con- 
tract itself  to  a  point ;  that  is,  though  we  may  imagine 
something  to  rise  where  before  was  nothing,  and  noth- 
ing to  be  there  where  before  was  something,  yet  we 
cannot  comprehend  in  our  mind  how  this  may  possibly 
be  done  in  nature.     And  therefore  philosophers,  who 
tie  themselves  to  natural  reason,  suppose  that  a  body 
can  neither  be  generated  nor  destroyed,  but  only  that 
it  may  appear  otherwise  than  it  did  to  us,  that  is,  under 
different  species,  and  consequently  be  called  by  other 
and  other  names ;  so  that  that  which  is  now  called  man, 
may  at  another  time  have  the  name  of  not-man ;  but 
that  which  is  once  called  body,  can  never  be  called  not- 
body.     But  it  is  manifest,  that  all  other  accidents  be- 
sides magnitude  or  extension  may  be  generated  and  de- 
stroyed; as  when  a  white   thing  is  made  black,  the 
whiteness  that  was  in  it  perisheth,  and  the  blackness 
that  was  not  in  it  is  now  generated ;  and  therefore  bod- 
ies,   and    the    accidents    under    which    they    appear 
diversely,  have  this  difference,  that  bodies  are  things, 
and  not  generated;  accidents  are  generated,  and  not 
things. 

21.  And  therefore,  when  any  thing  appears  other- 
wise than  it  did  by  reason  of  other  and  other  acci- 
dents, it  is  not  to  be  thought  that  an  accident  goes  out 


OF  BODY  AND  ACCIDENT.  67 

of  one  subject  into  another,  (for  they  are  not,  as  I 
said  above,  in  their  subjects  as  a  part  in  the  whole,  or 
as  a  contained  thing  in  that  which  contains  it,  or  as  a 
master  of  a  family  in  his  house,)  but  that  one  accident 
perisheth,  and  another  is  generated.  For  example, 
when  the  hand,  being  moved,  moves  the  pen,  motion 
does  not  go  out  of  the  hand  into  the  pen;  for  so  the 
writing  might  be  continued  though  the  hand  stood 
still ;  but  a  new  motion  is  generated  in  the  pen,  and  is 
the  pen's  motion. 

22.  And  therefore  also  it  is  improper  to  say,  an 
accident  is  moved;  as  when,  instead  of  saying,  figure 
is  an  accident  of  a  body  carried  azvay,  we  say,  a  body 
carries  azvay  its  figure. 

23.  Now  that  accident  for  which  we  give  a  certain 
name  to  any  body,  or  the  accident  which  denominates  its 
subject,  is  commonly  called  the  essence  thereof;  as 
rationality  is  the  essence  of  a  man ;  whiteness,  of  any 
white  thing,  and  extension  the  essence  of  a  body.  And 
the  same  essence,  in  as  much  as  it  is  generated,  is  called 
the  form.  Again,  a  body,  in  respect  of  any  accident, 
is  called  the  subject,  and  in  respect  of  the  form  it  is 
called  the  matter. 

Also,  the  production  or  perishing  of  any  accident 
makes  its  subject  be  said  to  be  changed;  only  the  pro- 
duction or  perishing  of  form  makes  it  be  said  it  is 
generated  or  destroyed;  but  in  all  generation  and  muta- 
tion, the  name  of  matter  still  remains.  For  a  table 
made  of  wood  is  not  only  wooden,  but  wood;  and  a 
statue  of  brass  is  brass  as  well  as  brazen;  though 
Aristotle,  in  his  Metaphysics,  says  that  whatsoever  is 
made  of  any  thing  ought  not  to  be  called  Ikuvo;  but 
cKeivtvov ;  as  that  which  is  made  of  wood,  not  £v\ov 
but  ivXivov ,  that  is,  not  wood,  but  wooden. 


68  CONCERNING  BODY. 

24.  And  as  for  that  matter  which  is  common  to  all 
things,  and  which  philosophers,  following  Aristotle, 
usually  call  materia  prima,  that  is,  first  matter,  it  is  not 
any  body  distinct  from  all  other  bodies,  nor  is  it  one  of 
them.  What  then  is  it?  A  mere  name;  yet  a  name 
which  is  not  of  vain  use;  for  it  signifies  a  conception 
of  body  without  the  consideration  of  any  form  or  other 
accident  except  only  magnitude  or  extension,  and  apt- 
ness to  receive  form  and  other  accident.  So  that  when- 
soever we  have  use  of  the  name  body  in  general,  if  we 
use  that  of  materia  prima,  we  do  well.  For  as  when  a 
man  not  knowing  which  was  first,  water  or  ice,  would 
find  out  which  of  the  two  were  the  matter  of  both,  he 
would  be  fain  to  suppose  some  third  matter  which  were 
neither  of  these  two ;  so  he  that  would  find  out  what  is 
the  matter  of  all  things,  ought  to  suppose  such  as  is 
not  the  matter  of  anything  that  exists.  Wherefore 
materia  prima  is  nothing;  and  therefore  they  do  not 
attribute  to  it  either  form  or  any  other  accident  besides 
quantity;  whereas  all  singular  things  have  their  forms 
and  accidents  certain. 

Materia  prima,  therefore,  is  body  in  general,  that  is, 
body  considered  universally,  not  as  having  neither 
form  nor  any  accident,  but  in  which  no  form  nor  any 
other  accident  but  quantity  are  at  all  considered,  that 
is,  they  are  not  drawn  into  argumentation. 

25.  From  what  has  been  said,  those  axioms  may  be 
demonstrated,  which  are  assumed  by  Euclid  in  the  be- 
ginning of  his  first  element,  about  the  equality  and  in- 
equality of  magnitudes;  of  which,  omitting  the  rest,  I 
will  here  demonstrate  only  this  one,  the  whole  is 
greater  than  any  part  thereof ;  to  the  end  that  the 
reader  may  know  that  those  axioms  are  not  indemon- 
strable, and  therefore  not  principles  of  demonstration ; 


OF  CAUSE  AND  EFFECT.  69 

and  from  hence  learn  to  be  wary  how  he  admits  any 
thing  for  a  principle,  which  is  not  at  least  as  evident  as 
these  are.  Greater  is  denned  to  be  that,  whose  part  is 
equal  to  the  whole  of  another.  Now  if  we  suppose  any 
whole  to  be  A,  and  a  part  of  it  to  be  B ;  seeing  the 
whole  B  is  equal  to  itself,  and  the  same  B  is  a  part  of 
A ;  therefore  a  part  of  A  will  be  equal  to  the  whole  B. 
Wherefore,  by  the  definition  above,  A  is  greater  than 
B ;  which  was  to  be  proved. 

CHAPTER  IX. 

OF   CAUSE   AND  EFFECT. 

I.  Action  and  passion,  what  they  are.— 2.  Action  and  passion 
mediate  and  immediate. — 3.  Cause  simply  taken.  Cause 
without  which  no  effect  follows,  or  cause  necessary  by  sup- 
position.— 4.  Cause  efficient  and  material. — 5.  An  entire 
cause  is  always  sufficient  to  produce  its  effect.  At  the  same 
instant  that  the  cause  is  entire,  the  effect  is  produced. 
Every  effect  has  a  necessary  cause. — 6.  The  generation  of 
effects  is  continual.  What  is  the  beginning  in  causation. — 7. 
No  cause  of  motion  but  in  a  body  contiguous  and  moved. — 
8.  The  same  agents  and  patients,  if  alike  disposed,  produce 
like  effects  though  at  different  times. — 9.  All  mutation  is 
motion. — 10.  Contingent  accidents,  what  they  are. 

I.  A  body  is  said  to  wrork  upon  or  act,  that  is  to  say, 
do  something  to  another  body,  when  it  either  generates 
or  destroys  some  accident  in  it :  and  the  body  in  which 
an  accident  is  generated  or  destroyed  is  said  to  suffer, 
that  is,  to  have  something  done  to  it  by  another  body ; 
as  when  one  body  by  putting  forwards  another  body 
generates  motion  in  it,  it  is  called  the  agent  ;  and  the 
body  in  which  motion  is  so  generated,  is  called  the 
patient  ;  so  fire  that  warms  the  hand  is  the  agent,  and 


;o  CONCERNING  BODY. 

the  hand,  which  is  warmed,  is  the  patient.     That  acci- 
dent, which  is  generated  in  the  patient,  is  called  the 

EFFECT. 

2.  When  an  agent  and  patient  are  contiguous  to 
one  another,  their  action  and  passion  are  then  said  to 
be  immediate,  otherwise,  mediate;  and  when  another 
body,  lying  betwixt  the  agent  and  patient,  is  contigu- 
ous to  them  both,  it  is  then  itself  both  an  agent  and  a 
patient ;  an  agent  in  respect  of  the  body  next  after  it, 
upon  which  it  works,  and  a  patient  in  respect  of  the 
body  next  before  it,  from  which  it  suffers.  Also,  if 
many  bodies  be  so  ordered  that  every  two  which  are 
next  to  one  another  be  contiguous,  then  all  those  that 
are  betwixt  the  first  and  the  last  are  both  agents  and 
patients,  and  the  first  is  an  agent  only,  and  the  last  a 
patient  only. 

3.  An  agent  is  understood  to  produce  its  deter- 
mined or  certain  effect  in  the  patient,  according  to 
some  certain  accident  or  accidents,  with  which  both  it 
and  the  patient  are  affected;  that  is  to  say,  the  agent 
hath  its  effect  precisely  such,  not  because  it  is  a  body, 
but  because  such  a  body,  or  so  moved.  For  otherwise 
all  agents,  seeing  they  are  all  bodies  alike,  would  pro- 
duce like  effects  in  all  patients.  And  therefore  the 
fire,  for  example,  does  not  warm,  because  it  is  a  body, 
but  because  it  is  hot ;  nor  does  one  body  put  forward 
another  body  because  it  is  a  body,  but  because  it  is 
moved  into  the  place  of  that  other  body.  The  cause, 
therefore,  of  all  effects  consists  in  certain  accidents 
both  in  the  agents  and  in  the  patients;  which  when 
they  are  all  present,  the  effect  is  produced ;  but  if  any 
one  of  them  be  wanting,  it  is  not  produced ;  and  that 
accident  either  of  the  agent  or  patient,  without  which 
the  effect  cannot  be  produced,  is  called  causa  sine  qua 


OF  CAUSE  AND  EFFECT.  71 

non,  or  cause  necessary  by  supposition,  as  also  the 
cause  requisite  for  the  production  of  the  effect.  But  a 
cause  simply,  or  an  entire  cause,  is  the  aggregate  of 
all  the  accidents  both  of  the  agents  how  many  soever 
they  be,  and  of  the  patient,  put  together;  which  when 
they  are  all  supposed  to  be  present,  it  cannot  be  under- 
stood but  that  the  effect  is  produced  at  the  same  in- 
stant; and  if  any  one  of  them  be  wanting,  it  cannot  be 
understood  but  that  the  effect  is  not  produced. 

4.  The  aggregate  of  accidents  in  the  agent  or 
agents,  requisite  for  the  production  of  the  effect,  the 
effect  being  produced,  is  called  the  efficient  cause 
thereof;  and  the  aggregate  of  accidents  in  the  patient, 
the  effect  being  produced,  is  usually  called  the 
material  cause;  I  say  the  effect  being  produced;  for 
where  there  is  no  effect  there  can  be  no  cause;  for 
nothing  can  be  called  a  cause,  where  there  is  nothing 
that  can  be  called  an  effect.  But  the  efficient  and 
material  causes  are  both  but  partial  causes,  or  parts  of 
that  cause,  which  in  the  next  precedent  article  I  called 
an  entire  cause.  And  from  hence  it  is  manifest,  that 
the  effect  we  expect,  though  the  agents  be  not  defective 
on  their  part,  may  nevertheless  be  frustrated  by  a 
defect  in  the  patient ;  and  when  the  patient  is  sufficient, 
by  a  defect  in  the  agents. 

5.  An  entire  cause  is  always  sufficient  for  the  pro- 
duction of  its  effect,  if  the  effect  be  at  all  possible.  For 
let  any  effect  whatsoever  be  propounded  to  be  pro- 
duced ;  if  the  same  be  produced,  it  is  manifest  that  the 
cause  which  produced  it  was  a  sufficient  cause;  but  if 
it  be  not  produced,  and  yet  be  possible,  it  is  evident 
that  something  was  wanting  either  in  some  agent,  or 
in  the  patient,  without  which  it  could  not  be  produced ; 
that  is,  that  some  accident  was  wanting  which  was 


72  CONCERNING  BODY. 

requisite  for  its  production;  and  therefore,  that  cause 
was  not  entire,  which  is  contrary  to  what  was  sup- 
posed. 

It  follows  also  from  hence,  that  in  whatsoever  in- 
stant the  cause  is  entire,  in  the  same  instant  the  effect 
is  produced.  For  if  it  be  not  produced,  something  is 
still  wanting,  which  is  requisite  for  the  production  of 
it;  and  therefore  the  cause  was  not  entire,  as  was 
supposed. 

And  seeing  a  necessary  cause  is  defined  to  be  that, 
which  being  supposed,  the  effect  cannot  but  follow; 
this  also  may  be  collected,  that  whatsoever  effect  is 
produced  at  any  time,  the  same  is  produced  by  a  neces- 
sary cause.  For  whatsoever  is  produced,  in  as  much 
as  it  is  produced,  had  an  entire  cause,  that  is,  had  all 
those  things,  which  being  supposed,  it  cannot  be  under- 
stood but  that  the  effect  follows ;  that  is,  it  had  a 
necessary  cause.  And  in  the  same  manner  it  may  be 
shewn,  that  whatsoever  effects  are  hereafter  to  be  pro- 
duced, shall  have  a  necessary  cause;  so  that  all  the 
effects  that  have  been,  or  shall  be  produced,  have  their 
necessity  in  things  antecedent. 

6.  And  from  this,  that  whensoever  the  cause  is 
entire,  the  effect  is  produced  in  the  same  instant,  it  is 
manifest  that  causation  and  the  production  of  effects 
consist  in  a  certain  continual  progress ;  so  that  as  there 
is  a  continual  mutation  in  the  agent  or  agents,  by  the 
working  of  other  agents  upon  them,  so  also  the  patient, 
upon  which  they  work,  is  continually  altered  and 
changed.  For  example:  as  the  heat  of  the  fire  in- 
creases more  and  more,  so  also  the  effects  thereof, 
namely,  the  heat  of  such  bodies  as  are  next  to  it,  and 
again,  of  such  other  bodies  as  are  next  to  them,  increase 
more  and  more  accordingly;  which  is  already  no  little 


OF  CAUSE  AND  EFFECT.  n 

argument  that  all  mutation  consists  in  motion  only; 
the  truth  whereof  shall  be  further  demonstrated  in  the 
ninth  article.  But  in  this  progress  of  causation,  that 
is,  of  action  and  passion,  if  any  man  comprehend  in 
his  imagination  a  part  thereof,  and  divide  the  same  into 
parts,  the  first  part  or  beginning  of  it  cannot  be  con- 
sidered otherwise  than  as  action  or  cause;  for,  if  it 
should  be  considered  as  effect  or  passion,  then  it  would 
be  necessary  to  consider  something  before  it,  for  its 
cause  or  action;  which  cannot  be,  for  nothing  can  be 
before  the  beginning.  And  in  like  manner,  the  last 
part  is  considered  only  as  effect ;  for  it  cannot  be 
called  cause,  if  nothing  follow  it;  but  after  the  last, 
nothing  follows.  And  from  hence  it  is,  that  in  all 
action  the  beginning  and  cause  are  taken  for  the  same 
thing.  But  every  one  of  the  intermediate  parts  are 
both  action  and  passion,  and  cause  and  effect,  accord- 
ing as  they  are  compared  with  the  antecedent  or  subse- 
quent part. 

7.  There  can  be  no  cause  of  motion,  except  in  a 
body  contiguous  and  moved.  For  let  there  be  any  two' 
bodies  which  are  not  contiguous,  and  betwixt  which 
the  intermediate  space  is  empty,  or,  if  filled,  filled  with 
another  body  which  is  at  rest;  and  let  one  of  the  pro- 
pounded bodies  be  supposed  to  be  at  rest ;  I  say  it  shall 
always  be  at  rest.  For  it  if  shall  be  moved,  the  cause 
of  that  motion,  by  the  8th  chapter,  article  19,  will  be 
some  external  body;  and,  therefore,  if  between  it  and 
that  external  body  there  be  nothing  but  empty  space, 
then  whatsoever  the  disposition  be  of  that  external 
body  or  of  the  patient  itself,  yet  if  it  be  supposed  to  be 
now  at  rest,  we  may  conceive  it  will  continue  so  till  it 
be  touched  by  some  other  body,    But  seeing  cause,  by 


74  CONCERNING  BODY. 

the  definition,  is  the  aggregate  of  all  such  accidents, 
which  being  supposed  to  be  present,  it  cannot  be  con- 
ceived but  that  the  effect  will  follow,  those  accidents, 
which  are  either  in  external  bodies,  or  in  the  patient  it- 
self, cannot  be  the  cause  of  future  motion.  And  in  like 
manner,  seeing  we  may  conceive  that  whatsoever  is  at 
rest  will  still  be  at  rest,  though  it  be  touched  by  some 
other  body,  except  that  other  body  be  moved;  there- 
fore in  a  contiguous  body,  which  is  at  rest,  there  can 
be  no  cause  of  motion.  Wherefore  there  is  no  cause 
of  motion  in  any  body,  except  it  be  contiguous  and 
moved. 

The  same  reason  may  serve  to  prove  that  whatsoever 
is  moved,  will  always  be  moved  on  in  the  same  way 
and  with  the  same  velocity,  except  it  be  hindered  by 
some  other  contiguous  and  moved  body;  and  conse- 
quently that  no  bodies,  either  when  they  are  at  rest,  or 
when  there  is  an  interposition  of  vacuum,  can  generate 
or  extinguish  or  lessen  motion  in  other  bodies.  There 
is  one  that  has  written  that  things  moved  are  more  re- 
sisted by  things  at  rest,  than  by  things  contrarily 
moved;  for  this  reason,  that  he  conceived  motion  not 
to  be  so  contrary  to  motion  as  rest.  That  which  de- 
ceived him  was,  that  the  words  rest  and  motion  are  but 
contradictory  names;  whereas  motion,  indeed,  is  not 
resisted  by  rest,  but  by  contrary  motion. 

8.  But  if  a  body  work  upon  another  body  at  one 
time,  and  afterwards  the  same  body  work  upon  the 
same  body  at  another  time,  so  that  both  the  agent  and 
patient,  and  all  their  parts,  be  in  all  things  as  they  were ; 
and  there  be  no  difference,  except  only  in  time,  that  is, 
that  one  action  be  former,  the  other  later  in  time ;  it  is 
manifest  of  itself,  that  the  effects  will  be  equal  and 
like,  as  not  differing  in  anything  besides  time.     And 


OF  CAUSE  AND  EFFECT.  75 

as  effects  themselves  proceed  from  their  causes,  so  the 
diversity  of  them  depends  upon  the  diversity  of  their 
causes  also. 

9.  This  being  true,  it  is  necessary  that  mutation 
can  be  nothing  else  but  motion  of  the  parts  of  that 
body  which  is  changed.  For  first,  we  do  not  say  any- 
thing is  changed,  but  that  which  appears  to  our  senses 
otherwise  than  it  appeared  formerly.  Secondly,  both 
those  appearances  are  effects  produced  in  the  sentient; 
and,  therefore,  if  they  be  different,  it  is  necessary,  by 
the  preceding  article,  that  either  some  part  of  the 
agent,  which  was  formerly  at  rest,  is  now  moved,  and 
so  the  mutation  consists  in  this  motion ;  or  some  part, 
which  was  formerly  moved,  is  now  otherwise  moved, 
and  so  also  the  mutation  consists  in  this  new  motion; 
or  which,  being  formerly  moved,  is  now  at  rest,  which, 
as  I  have  shewn  above,  cannot  come  to  pass  without 
motion;  and  so  again,  mutation  is  motion;  or  lastly, 
it  happens  in  some  of  these  manners  to  the  patient,  or 
some  of  its  parts;  so  that  mutation,  howsoever  it  be 
made,  will  consist  in  the  motion  of  the  parts,  either  of 
the  body  which  is  perceived,  or  of  the  sentient  body, 
or  of  both.  Mutation  therefore  is  motion,  namely,  of 
the  parts  either  of  the  agent  or  of  the  patient;  which 
was  to  be  demonstrated.  And  to  this  it  is  consequent, 
that  rest  cannot  be  the  cause  of  anything,  nor  can  any 
action  proceed  from  it;  seeing  neither  motion  nor 
mutation  can  be  caused  by  it. 

10.  Accidents,  in  respect  of  other  accidents  which 
precede  them,  or  are  before  them  in  time,  and  upon 
which  they  do  not  depend  as  upon  their  causes,  are 
called  contingent  accidents ;  I  say,  in  respect  of  those 
accidents  by  which  they  are  not  generated;  for,  in 
respect  of  their  causes,  all  things  come  to  pass  with 


76  CONCERNING  BODY. 

equal  necessity;  for  otherwise  they  would  have  no 
causes  at  ail;  which,  of  things  generated,  is  not  in- 
telligible. 

CHAPTER  X. 

OF  POWER  AND  ACT. 

I.  Power  and  cause  are  the  same  thing. — 2.  An  act  is  pro- 
duced at  the  same  instant  in  which  the  power  is  plenary. — 
3.  Active  and  passive  power  are  parts  only  of  plenary  power. 
— 4.  An  act,  when  said  to  be  possible. — 5.  An  act  necessary 
and  contingent,  what. — 6.  Active  power  consists  in  motion. — 
7.  Cause,  formal  and  final,  what  they  are. 

i.  Correspondent  to  cause  and  effect,  are  power 
and  act;  nay,  those  and  these  are  the  same  things; 
though,  for  divers  considerations,  they  have  divers 
names.  For  whensoever  any  agent  has  all  those  acci- 
dents which  are  necessarily  requisite  for  the  produc- 
tion of  some  effect  in  the  patient,  then  we  say  that  agent 
has  power  to  produce  that  effect,  if  it  be  applied  to  a  pa- 
tient. But,  as  I  have  shewn  in  the  precedent  chapter, 
those  accidents  constitute  the  efficient  cause ;  and  there- 
fore the  same  accidents,  which  constitute  the  efficient 
cause,  constitute  also  the  power  of  the  agent.  Where- 
fore the  power  of  the  agent  and  the  efficient  cause  are 
the  same  thing.  But  they  are  considered  with  this  dif- 
ference, that  cause  is  so  called  in  respect  to  the  effect 
already  produced,  and  power  in  respect  of  the  same  ef- 
fect to  be  produced  hereafter;  so  that  cause  respects 
the  past,  power  the  future  time.  Also,  the  power  of 
the  agent  is  that  which  is  commonly  called  active 
power. 

In  like  manner,  whensoever  any  patient  has  all  those 


OF  POWER  AND  ACT.  77 

accidents  which  it  is  requisite  it  should  have,  for  the 
production  of  some  effect  in  it,  we  say  it  is  in  the 
power  of  that  patient  to  produce  that  effect,  if  it  be 
applied  to  a  fitting  agent.  But  those  accidents,  as  is 
defined  in  the  precedent  chapter,  constitute  the  material 
cause;  and  therefore  the  power  of  the  patient,  com- 
monly called  passive  pozver,  and  material  cause,  are  the 
same  thing;  but  with  this  different  consideration,  that 
in  cause  the  past  time,  and  in  power  the  future,  is 
respected.  Wherefore  the  power  of  the  agent  and 
patient  together,  which  may  be  called  entire  or  plenary 
pozver,  is  the  same  thing  with  entire  cause;  for  they 
both  consist  in  the  sum  or  aggregate  of  all  the  acci- 
dents, as  well  in  the  agent  as  in  the  patient,  which  are 
requisite  for  the  production  of  the  effect.  Lastly,  as 
the  accident  produced  is,  in  respect  of  the  cause,  called 
an  effect,  so  in  respect  of  the  power,  it  is  called  an  act. 

2.  As  therefore  the  effect  is  produced  in  the  same 
instant  in  which  the  cause  is  entire,  so  also  every  act 
that  may  be  produced,  is  produced  in  the  same  instant 
in  which  the  power  is  plenary.  And  as  there  can  be 
no  effect  but  from  a  sufficient  and  necessary  cause,  so 
also  no  act  can  be  produced  but  by  sufficient  power,  or 
that  power  by  which  it  could  not  but  be  produced. 

3.  And  as  it  is  manifest,  as  I  have  shewn,  that  the 
efficient  and  material  causes  are  severally  and  by  them- 
selves parts  only  of  an  entire  cause,  and  cannot  produce 
any  effect  but  by  being  joined  together,  so  also  power, 
active  and  passive,  are  parts  only  of  plenary  and  entire 
power ;  nor,  except  they  be  joined,  can  any  act  proceed 
from  them;  and  therefore  these  powers,  as  I  said  in 
the  first  article,  are  but  conditional,  namely,  the  agent 
has  power,  if  it  be  applied  to  a  patient;  and  the  patient 
has  pozver,  if  it  be  applied  to  an  agent;  otherwise 


78  CONCERNING  BODY. 

neither  of  them  have  power,  nor  can  the  accidents, 
which  are  in  them  severally,  be  properly  called  powers ; 
nor  any  action  be  said  to  be  possible  for  the  power  of 
the  agent  alone  or  of  the  patient  alone. 

4.  For  that  is  an  impossible  act,  for  the  production 
of  which  there  is  no  power  plenary.  For  seeing  ple- 
nary power  is  that  in  which  all  things  concur,  which 
are  requisite  for  the  production  of  an  act,  if  the  power 
shall  never  be  plenary,  there  will  always  be  wanting 
some  of  those  things,  without  which  the  act  cannot  be 
produced ;  wherefore  that  act  shall  never  be  produced ; 
that  is,  that  act  is  impossible  :  and  every  act,  which  is 
not  impossible,  is  possible.  Every  act,  therefore, 
which  is  possible,  shall  at  some  time  be  produced ;  for 
if  it  shall  never  be  produced,  then  those  things  shall 
never  concur  which  are  requisite  for  the  production  of 
it;  wherefore  that  act  is  impossible,  by  the  definition; 
which  is  contrary  to  what  was  supposed. 

5.  A  necessary  act  is  that,  the  production  whereof 
it  is  impossible  to  hinder ;  and  therefore  every  act,  that 
shall  be  produced,  shall  necessarily  be  produced;  for, 
that  it  shall  not  be  produced,  is  impossible ;  because,  as 
is  already  demonstrated,  every  possible  act  shall  at 
some  time  be  produced;  nay,  this  proposition,  what 
shall  be,  shall  be,  is  as  necessary  a  proposition  as  this, 
a  man  is  a  man. 

But  here,  perhaps,  some  man  may  ask  whether  those 
future  things,  which  are  commonly  called  contingents, 
are  necessary.  I  say,  therefore,  that  generally  all  con- 
contingents  have  their  necessary  causes,  as  is  shewn  in 
the  preceding  chapter;  but  are  called  contingents  in 
respect  of  other  events,  upon  which  they  do  not  de- 
pend; as  the  rain,  which  shall  be  tomorrow,  shall  be 
necessary,  that  is,  from  necessary  causes ;  but  we  think 


OF  POWER  AND  ACT.  79 

and  say  it  happens  by  chance,  because  we  do  not  yet 
perceive  the  causes  thereof,  though  they  exist  now; 
for  men  commonly  call  that  casual  or  contingent, 
whereof  they  do  not  perceive  the  necessary  cause; 
and  in  the  same  manner  they  used  to  speak  of  things 
past,  when  not  knowing  whether  a  thing  be  done  or 
no,  they  say  it  is  possible  it  never  was  done. 

Wherefore,  all  propositions  concerning  future 
things,  contingent  or  not  contingent,  as  this,  it  will  rain 
tomorrow,  or  this,  tomorrow  the  sun  will  rise,  are 
either  necessarily  true,  or  necessarily  false ;  but  we  call 
them  contingent  because  we  do  not  yet  know  whether 
they  be  true  or  false ;  whereas  their  verity  depends  not 
upon  our  knowledge,  but  upon  the  foregoing  of  their 
causes.  But  there  are  some,  who  though  they  confess 
this  whole  proposition,  tomorrow  it  will  either  rain,  or 
not  rain,  to  be  true,  yet  they  will  not  acknowledge  the 
parts  of  it,  as,  tomorrow  it  unit  rain,  or,  tomorrow  it 
will  not  rain,  to  be  either  of  them  true  by  itself;  be- 
cause they  say  neither  this  nor  that  is  true  determi- 
nately.  But  what  is  this  determinatcly  true,  but  true 
upon  our  knowledge,  or  evidently  true?  And  there- 
fore they  say  no  more  but  that  it  is  not  yet  known 
whether  it  be  true  or  no ;  but  they  say  it  more  ob- 
scurely, and  darken  the  evidence  of  the  truth  with  the 
same  words,  with  which  they  endeavour  to  hide  their 
own  ignorance. 

6.  In  the  9th  article  of  the  preceding  chapter,  I 
have  shewn  that  the  efficient  cause  of  all  motion  and 
mutation  consists  in  the  motion  of  the  agent,  or  agents ; 
and  in  the  first  article  of  this  chapter,  that  the  power  of 
the  agent  is  the  same  thing  wTith  the  efficient  cause. 
From  whence  it  may  be  understood,  that  all  active 
power  consists  in  motion  also ;  and  that  power  is  not  a 


80  CONCERNING  BODY. 

certain  accident,  which  differs  from  all  acts,  but  is, 
indeed,  an  act,  namely,  motion,  which  is  therefore 
called  power,  because  another  act  shall  be  produced  by 
it  afterwards.  For  example,  if  of  three  bodies  the  first 
put  forward  the  second,  and  this  the  third,  the  motion 
of  the  second,  in  respect  of  the  first  which  produceth 
it,  is  the  act  of  the  second  body ;  but,  in  respect  of  the 
third,  it  is  the  active  power  of  the  same  second  body. 

7.  The  writers  of  metaphysics  reckon  up  two 
other  causes  besides  the  efficient  and  material,  namely, 
the  essence,  which  some  call  the  formal  cause,  and  the 
end,  or  final  cause;  both  which  are  nevertheless 
efficient  causes.  For  when  it  is  said  the  essence  of  a 
thing  is  the  cause  thereof,  as  to  be  rational  is  the  cause 
of  man,  it  is  not  intelligible ;  for  it  is  all  one,  as  if  it 
were  said,  to  be  a  man  is  the  cause  of  man;  which  is 
not  well  said.  And  yet  the  knowledge  of  the  essence 
of  anything,  is  the  cause  of  the  knowledge  of  the  thing 
itself;  for,  if  I  first  know  that  a  thing  is  rational,  I 
know  from  thence,  that  the  same  is  man;  but  this  is  no 
other  than  an  efficient  cause.  A  final  cause  has  no 
place  but  in  such  things  as  have  sense  and  will;  and 
this  also  I  shall  prove  hereafter  to  be  an  efficient  cause. 

CHAPTER  XL 

OF  IDENTITY  AND  DIFFERENCE. 

I.  What  it  is  for  one  thing  to  differ  from  another. — 2.  To 
differ  in  number,  magnitude,  species,  and  genus,  what. — 3. 
What  is  relation,  proportion,  and  relatives. — 4.  Proportion- 
als, what. — 5.  The  proportion  of  magnitudes  to  one  another, 
wherein  it  consists. — 6.  Relation  is  no  new  accident,  but  one 
of  those  that  were  in  the  relative  before  the  relation  or 
comparison  was  made.    Also  the  causes  of  accidents  in  the 


OF  IDENTITY  AND  DIFFERENCE.  81 

correlatives,  are  the  cause  of  relation.— 7.  Of  the  beginning 
of  individuation. 

1.  Hitherto  I  have  spoken  of  body  simply,  and 
accidents  common  to  all  bodies,  as  magnitude,  motion, 
rest,  action,  passion,  power,  possible,  &c. ;  and  I  should 
now  descend  to  those  accidents  by  which  one  body  is 
distinguished  from  another  but  that  it  is  first  to  be  de- 
clared what  it  is  to  be  distinct  and  not  distinct,  namely, 
what  are  the  same  and  different  ;  for  this  also  is  com- 
mon to  all  bodies,  that  they  may  be  distinguished  and 
differenced  from  one  another.  Now,  two  bodies  are 
said  to  differ  from  one  another,  when  something  may 
be  said  of  one  of  them,  which  cannot  be  said  of  the 
other  at  the  same  time. 

2.  And,  first  of  all,  it  is  manifest  that  no  two  bodies 
are  the  same;  for  seeing  they  are  two,  they  are  in  two 
places  at  the  same  time ;  as  that,  which  is  the  same,  is 
at  the  same  time  in  one  and  the  same  place.  All  bodies 
therefore  differ  from  one  another  in  number,  namely, 
as  one  another ;  so  that  the  same  and  different  in  num- 
ber, are  names  opposed  to  one  another  by  contradic- 
tion. 

In  magnitude  bodies  differ  when  one  is  greater  than 
another,  as  a  cubit  long,  and  two  cubits  long,  of  two 
pound  weight,  and  of  three  pound  weight.  And  to 
these,  equals  are  opposed. 

Bodies  which  differ  more  than  in  magnitude,  are 
called  unlike;  and  those,  which  differ  only  in  magni- 
tude, like.  Also,  of  unlike  bodies,  some  are  said  to 
differ  in  the  species,  other  in  the  genus;  in  the  species, 
when  their  difference  is  perceived  by  one  and  the  same 
sense,  as  white  and  black;  and  in  the  genus,  when  their 


82  CONCERNING  BODY. 

difference   is  not  perceived  but  by  divers  senses,  as 
white  and  hot. 

3.  And  the  likeness,  or  unlikeness,  equality,  or  in- 
equality of  one  body  to  another,  is  called  their  rela- 
tion ;  and  the  bodies  themselves  relatives  or  correla- 
tives; Aristotle  calls  them  rd  tt/dos  tI;  the  first  whereof 
is  usually  named  the  antecedent,  and  the  second  the 
consequent;  and  the  relation  of  the  antecedent  to  the 
consequent,  according  to  magnitude,  namely,  the  equal- 
ity, the  excess  or  defect  thereof,  is  called  the  propor- 
tion of  the  antecedent  to  the  consequent ;  so  that  pro- 
portion is  nothing  but  the  equality  or  inequality  of  the 
magnitude  of  the  antecedent  compared  to  the  magni- 
tude of  the  consequent  by  their  difference  only,  or  com- 
pared also  with  their  difference.  For  example, 
the  proportion  of  three  to  two  consists  only  in 
this,  that  three  exceeds  two  by  unity;  and  the 
proportion  of  two  to  five  in  this,  that  two,  compared 
with  five,  is  deficient  of  it  by  three,  either  simply,  or 
compared  with  the  numbers  different ;  and  therefore  in 
the  proportion  of  unequals,  the  proportion  of  the  less  to 
the  greater,  is  called  defect  ;  and  that  of  the  greater  to 
the  less,  excess. 

4.  Besides,  of  unequals,  some  are  more,  some  less, 
and  some  equally  unequal;  so  that  there  is  proportion 
of  proportions,  as  well  as  of  magnitudes ;  namely, 
where  two  unequals  have  relation  to  two  other  un- 
equals ;  as,  when  the  inequality  which  is  between  2  and 
3,  is  compared  with  the  inequality  which  is  between 
4  and  5.  In  which  comparison  there  are  always  four 
magnitudes ;  or,  which  is  all  one,  if  there  be  but  three, 
the  middle  most  is  twice  numbered ;  and  if  the  propor- 
tion of  the  first  to  the  second,  be  equal  to  the  propor- 
tion of  the  third  to  the  fourth,  then  the  four  are  said 


c* 


OF  IDENTITY  AND  DIFFERENCE.  83 

to  be  proportionals;  otherwise  they  are  not  propor- 
tionals. 

5.  The  proportion  of  the  antecendent  to  the  conse- 
quent consists  in  their  difference,  not  only  simply  taken, 
but  also  as  compared  with  one  of  the  relatives ;  that  is, 
either  in  that  part  of  the  greater,  by  which  it  exceeds 
the  less,  or  in  the  remainder,  after  the  less  is  taken  out 
of  the  greater ;  as  the  proportion  of  two  to  five  consists 
in  the  three  by  which  five  exceeds  two,  not  in  three 
simply  only,  but  also  as  compared  with  five  or  two. 
For  though  there  be  the  same  difference  between  two 
and  five,  which  is  between  nine  and  twelve,  namely 
three,  yet  there  is  not  the  same  inequality ;  and  there- 
fore the  proportion  of  two  to  five  is  not  in  all  relation 
the  same  with  that  of  nine  to  twelve,  but  only  in  that 
which  is  called  arithmetical. 

6.  But  we  must  not  so  think  of  relation,  as  if  it 
were  an  accident  differing  from  all  the  other  accidents 
of  the  relative ;  but  one  of  them,  namely,  that  by  which 
the  comparison  is  made.  For  example,  the  likeness  of 
one  white  to  another  white,  or  its  unlikeness  to  black, 
is  the  same  accident  with  its  whiteness;  and  equality 
and  inequality,  the  same  accident  with  the  magnitude 
of  the  thing  compared,  though  under  another  name: 
for  that  which  is  called  white  or  great,  when  it  is  not 
compared  with  something  else,  the  same  when  it  is 
compared,  is  called  like  or  unlike,  equal  or  unequal. 
And  from  this  it  follows  that  the  causes  of  the  acci- 
dents, which  are  in  relatives,  are  the  causes  also  of 
likeness,  unlikeness,  equality  and  inequality;  namely, 
that  he,  that  makes  two  unequal  bodies,  makes  also 
their  inequality;  and  he,  that  makes  a  rule  and  an 
action,  makes  also,  if  the  action  be  congruous  to  the 
rule,  their  congruity;  if  incongruous,  their  incongru- 


84  CONCERNING  BODY. 

ity.     And  thus  much  concerning  comparison  of  one 
body  with  another. 

7.  But  the  same  body  may  at  different  times  be 
compared  with  itself.  And  from  hence  springs  a  great 
controversy  among  philosophers  about  the  beginning 
of  individuation,  namely,  in  what  sense  it  may  be  con- 
ceived that  a  body  is  at  one  time  the  same,  at  another 
time  not  the  same  it  was  formerly.  For  example, 
whether  a  man  grown  old  be  the  same  man  he  was 
whilst  he  was  young,  or  another  man;  or  whether  a 
city  be  in  different  ages  the  same,  or  another  city. 
Some  place  individuity  in  the  unity  of  matter;  others 
in  the  unity  of  form;  and  one  says  it  consists  in  the 
unity  of  the  aggregate  of  all  the  accidents  together. 
For  matter,  it  is  pleaded  that  a  lump  of  wax,  whether 
it  be  spherical  or  cubical,  is  the  same  wax,  because  the 
same  matter.  For  form,  that  when  a  man  is  grown 
from  an  infant  to  be  an  old  man,  though  his  matter 
be  changed,  yet  he  is  still  the  same  numerical  man; 
for  that  identity,  which  cannot  be  attributed  to  the  mat- 
ter, ought  probably  to  be  ascribed  to  the  form.  For 
the  aggregate  of  accidents,  no  instance  can  be  made ; 
but  because,  when  any  new  accident  is  generated,  a 
new  name  is  commonly  imposed  on  the  thing,  therefore 
he,  that  assigned  this  cause  of  individuity,  thought  the 
thing  itself  also  was  become  another  thing.  Accord- 
ing to  the  first  opinion,  he  that  sins,  and  he  that  is 
punished,  should  not  be  the  same  man,  by  reason  of 
the  perpetual  flux  and  change  of  man's  body;  nor 
should  the  city,  which  makes  laws  in  one  age  and 
abrogates  them  in  another,  be  the  same  city;  which 
were  to  confound  all  civil  rights.  According  to  the 
second  opinion,  two  bodies  existing  both  at  once, 
would  be  one  and  the  same  numerical  body.     For  if, 


OF  IDENTITY  AND  DIFFERENCE.  85 

for  example,  that  ship  of  Theseus,  concerning  the 
difference  whereof  made  by  continual  reparation  in 
taking  out  the  old  planks  and  putting  in  new,  the  soph- 
isters  of  Athens  were  wont  to  dispute,  were,  after  all 
the  planks  were  changed,  the  same  numerical  ship  it 
was  at  the  beginning;  and  if  some  man  had  kept  the 
old  planks  as  they  were  taken  out,  and  by  putting  them 
afterwards  together  in  the  same  order,  had  again  made 
a  ship  of  them,  this,  without  doubt,  had  also  been 
the  same  numerical  ship  with  that  which  was  at 
the  beginning;  and  so  there  would  have  been  two 
ships  numerically  the  same,  which  is  absurd.  But, 
according  to  the  third  opinion,  nothing  would  be  the 
same  it  was ;  so  that  a  man  standing  would  not  be  the 
same  he  was  sitting;  nor  the  water,  which  is  in 
the  vessel,  the  same  with  that  which  is  poured  out  of  it. 
Wherefore  the  beginning  of  individuation  is  not  always 
to  be  taken  either  from  matter  alone,  or  from  form 
alone. 

But  we  must  consider  by  what  name  anything  is 
called,  when  we  inquire  concerning  the  identity  of  it. 
For  it  is  one  thing  to  ask  concerning  Socrates,  whether 
he  be  the  same  man,  and  another  to  ask  whether  he 
be  the  same  body;  for  his  body,  when  he  is  old,  can- 
not be  the  same  it  was  when  he  was  an  infant,  by 
reason  of  the  difference  of  magnitude ;  for  one  body 
has  always  one  and  the  same  magnitude;  yet,  never- 
theless, he  may  be  the  same  man.  And  therefore, 
whensoever  the  name,  by  which  it  is  asked  whether 
a  thing  be  the  same  it  was,  is  given  it  for  the  matter 
only,  then,  if  the  matter  be  the  same,  the  thing  also 
is  individually  the  same;  as  the  water,  which  was  in 
the  sea,  is  the  same  which  is  afterwards  in  the  cloud; 
and  any  body  is  the  same,  whether  the  parts  of  it  be 


86  CONCERNING  BODY. 

put  together,  or  dispersed ;  or  whether  it  be  congealed, 
or  dissolved.  Also,  if  the  name  be  given  for  such 
form  as  is  the  beginning  of  motion,  then,  as  long  as 
that  motion  remains,  it  will  be  the  same  individual 
thing;  as  that  man  will  be  always  the  same,  whose  ac- 
tions and  thoughts  proceed  all  from  the  same  begin- 
ning of  motion,  namely,  that  which  was  in  his  genera- 
tion ;  and  that  will  be  the  same  river  which  flows  from 
one  and  the  same  fountain,  whether  the  same  water, 
or  other  water,  or  something  else  than  water,  flow  from 
thence;  and  that  the  same  city,  whose  acts  proceed 
continually  from  the  same  institution,  whether  the 
men  be  the  same  or  no.  Lastly,  if  the  name  be  given 
for  some  accident,  then  the  identity  of  the  thing  will 
depend  upon  the  matter ;  for,  by  the  taking  away  and 
supplying  of  matter,  the  accidents  that  were,  are  de- 
stroyed, and  other  new  ones  are  generated,  which 
cannot  be  the  same  numerically;  so  that  a  ship,  which 
signifies  matter  so  figured,  will  be  the  same  as  long 
as  the  matter  remains  the  same;  but  if  no  part  of 
the  matter  be  the  same,  then  it  is  numerically  another 
ship;  and  if  part  of  the  matter  remain  and  part  be 
changed,  then  the  ship  will  be  partly  the  same,  and 
partly  not  the  same. 

CHAPTER  XII*. 

OF    QUANTITY. 

I.  The  definition  of  quantity. — 2.  The  exposition  of  quantity, 
what  it  is.— 3.  How  line,  superficies,  and  solid  are  exposed. 
4.  How   time  is   exposed.— 5.  How  number   is   exposed.— 6. 


*  For  list   of  the  writings   of  Hobbes   on   mathematics,   cf. 
P-  xviii. 


OF  QUANTITY.  87 

How  velocity  is  exposed. — 7.  How  weight  is  exposed. — 8 
How  the  proportion  of  magnitudes  is  exposed. — 9.  How  the 
proportion  of  times  and  velocities  is  exposed. 

1.  What  and  how  manifold  dimension  is,  has  been 
said  in  the  8th  chapter,  namely,  that  there  are  three 
dimensions,  line  or  length,  superficies,  and  solid ;  every 
one  of  which,  if  it  be  determined,  that  is,  if  the  limits 
of  it  be  made  known,  is  commonly  called  quantity; 
for  by  quantity  all  men  understand  that  which  is  sig- 
nified by  that  word,  by  which  answer  is  made  to  the 
question,  How  much  is  it?  Whensoever,  therefore,  it 
is  asked,  for  example,  Hozv  long  is  the  journey  ?  it  is 
not  answered  indefinitely,  length;  nor,  when  it  is  asked, 
How  big  is  the  field?  is  it  answered  indefinitely,  super- 
ficies; nor,  if  a  man  ask,  How  great  is  the  bulk?  indefi- 
nitely, solid:  but  it  is  answered  determinately,  the  jour- 
ney is  a  hundred  miles ;  the  field  is  a  hundred  acres ; 
the  bulk  is  a  hundred  cubical  feet;  or  at  least  in 
some  such  manner,  that  the  magnitude  of  the  thing 
enquired  after  may  by  certain  limits  be  comprehended 
in  the  mind.  Quantity,  therefore,  cannot  otherwise 
be  defined,  than  to  be  a  dimension  determined,  or  a 
dimension,  whose  limits  are  set  out,  either  by  their 
place,  or  by  some  comparison. 

2.  And  quantity  is  determined  two  ways;  one,  by 
the  sense,  when  some  sensible  object  is  set  before  it; 
as  when  a  line,  a  superficies  or  solid,  of  a  foot  or  cubit, 
marked  out  in  some  matter,  is  objected  to  the  eyes; 
which  way  of  determining,  is  called  exposition,  and 
the  quantity  so  known  is  called  exposed  quantity;  the 
other  by  memory,  that  is,  by  comparison  with  some 
exposed  quantity.  In  the  first  manner,  when  it  is 
asked  of  what  quantity  a  thing  is,   it  is   answered, 


88  CONCERNING  BODY. 

of  such  quantity  as  you  see  exposed.  In  the  second 
manner,  answer  cannot  be  made  but  by  comparison 
with  some  exposed  quantity;  for  if  it  be  asked,  how 
long  is  the  way?  the  answer  is,  so  many  thousand 
paces;  that  is,  by  comparing  the  way  with  a  pace, 
or  some  other  measure,  determined  and  known  by 
exposition ;  or  the  quantity  of  it  is  to  some  other  quan- 
tity known  by  exposition,  as  the  diameter  of  a  square 
is  to  the  side  of  the  same,  or  by  some  other  the  like 
means.  But  it  is  to  be  understood,  that  the  quantity 
exposed  must  be  some  standing  or  permanent  thing, 
such  as  is  marked  out  in  consistent  or  durable  mat- 
ter ;  or  at  least  something  which  is  revocable  to  sense ; 
for  otherwise  no  comparison  can  be  made  by  it.  See- 
ing, therefore,  by  what  has  been  said  in  the  next  pre- 
ceding chapter,  comparison  of  one  magnitude  with 
another  is  the  same  thing  with  proportion ;  it  is  mani- 
fest, that  quantity  determined  in  the  second  manner 
is  nothing  else  but  the  proportion  of  a  dimension  not 
exposed  to  another  which  is  exposed;  that  is,  the 
comparison  of  the  equality  or  inequality  thereof  with 
an  exposed  quantity. 

3.  Lines,  superficies,  and  solids,  are  exposed,  first, 
by  motion,  in  such  manner  as  in  the  8th  chapter  I  have 
said  they  are  generated ;  but  so  as  that  the  marks 
of  such  motion  be  permanent;  as  when  they  are  de- 
signed upon  some  matter,  as  a  line  upon  paper;  or 
graven  in  some  durable  matter.  Secondly,  by  appo- 
sition; as  when  one  line  or  length  is  applied  to  another 
line  or  length,  one  breadth  to  another  breadth,  and 
one  thickness  to  another  thickness ;  which  is  as  much 
as  to  describe  a  line  by  points,  a  superficies  by  lines, 
and  a  solid  by  superficies ;  saving  that  by  points  in  this 
place  are  to  be  understood  very  short  lines;  and,  by 


OF  QUANTITY.  89 

superficies,  very  thin  solids,  thirdly,  lines  and  super- 
ficies may  be  exposed  by  section,  namely,  a  line  may  be 
made  by  cutting  an  exposed  superficies;  and  a  super- 
ficies, by  the  cutting  of  an  exposed  solid. 

4.  Time  is  exposed,  not  only  by  the  exposition  of 
a  line,  but  also  of  some  moveable  thing,  which  is 
moved  uniformly  upon  that  line,  or  at  least  is  sup- 
posed so  to  be  moved.  For,  seeing  time  is  an  idea 
of  motion,  in  which  we  consider  former  and  latter,  that 
is  succession,  it  is  not  sufficient  for  the  exposition  of 
time  that  a  line  be  described;  but  we  must  also  have 
in  our  mind  an  imagination  of  some  moveable  thing 
passing  over  that  line;  and  the  motion  of  it  must  be 
uniform,  that  time  may  be  divided  and  compounded 
as  often  as  there  shall  be  need.  And,  therefore,  when 
philosophers,  in  their  demonstrations,  draw  a  line, 
and  say,  Let  that  line  be  time,  it  is  to  be  understood  as 
if  they  said,  Let  the  conception  of  uniform  motion  upon 
that  line,  be  time.  For  though  the  circles  in  dials  be 
lines,  yet  they  are  not  of  themselves  sufficient  to  note 
time  by,  except  also  there  be,  or  be  supposed  to  be, 
a  motion  of  the  shadow  or  the  hand. 

5.  Number  is  exposed,  either  by  the  exposition  of 
points,  or  of  the  names  of  number,  one,  tzvo,  three, 
&c;  and  those  points  must  not  be  contiguous,  so  as 
that  they  cannot  be  distinguished  by  notes,  but  they 
must  be  so  placed  that  they  may  be  discerned  one  from 
another;  for,  from  this  it  is,  that  number  is  called 
discreet  quantity,  whereas  all  quantity,  which  is  de- 
signed by  motion,  is  called  continual  quantity.  But 
that  number  may  be  exposed  by  the  names  of  number, 
it  is  necessary  that  they  be  recited  by  heart  and  in 
order,  as  one,  two,  three,  &c. ;  for  by  saying  one, 
one,  one,  and  so  forward,  we  know  not  what  number 


90  CONCERNING  BODY. 

we  are  at  beyond  two  or  three;  which  also  appear  to 
us  in  this  manner  not  as  number,  but  as  figure. 

6.  For  the  exposition  of  velocity,  which,  by  the 
definition  thereof,  is  a  motion  which,  in  a  certain 
time,  passeth  over  a  certain  space,  it  is  requisite,  not 
only  that  time  be  exposed,  but  that  thero  be  also 
exposed  that  space  which  is  transmitted  by  the  body, 
whose  velocity  we  would  determine;  and  that  a  body 
be  understood  to  be  moved  in  that  space  also;  so  that 
there  must  be  exposed  two  lines,  upon  one  of  which 
uniform  motion  must  be  understood  to  be  made,  that 
the  time  may  be  determined;  and,  upon  the  other, 
the  velocity  is  to  be  computed.     As  if  we 

A B  WoUld  expose  the  velocity  of  the  body  A 

C  D  we  draw  two  lines  A  B  and  C  D,  and 

place  a  body  in  C  also;  which  done,  we 
say  the  velocity  of  the  body  A  is  so  great,  that  it 
passeth  over  the  line  A  B  in  the  same  time  in  which 
the  body  C  passeth  over  the  line  C  D  with  uniform 
motion. 

7.  Weight  is  exposed  by  any  heavy  body,  of  what 
matter  soever,  so  it  be  always  alike  heavy. 

8.  The  proportion  of  two  magnitudes  is  then  ex- 
posed, when  the  magnitudes  themselves  are  exposed, 
namely,  the  proportion  of  equality,  when  the  magni- 
tudes are  equal;  and  of  inequality,  when  they  are 
unequal.  For  seeing,  by  the  5th  article  of  the  pre- 
ceding chapter,  the  proportion  of  two  unequal  mag- 
nitudes consists  in  their  difference,  compared  with 
either  of  them ;  and  when  two  unequal  magnitudes  are 
exposed,  their  difference  is  also  exposed;  it  follows, 
that  when  magnitudes,  which  have  proportion  to  one 
another,  are  exposed,  their  proportion  also  is  ex- 
posed with  them;  and,  in  like  manner,  the  proportion 


OF  QUANTITY.  91 

of  equals,  which  consists  in  this,  that  there  is  no 
difference  of  magnitude  betwixt  them,  is  exposed  at 
the  same  time  when  the  equal  magnitudes  themselves 
are  exposed.  For  example,  if  the  exposed  lines  A  B 
and  C  D  be  equal,  the  proportion  of 
equality  is  exposed  in  them ;  and  if  the 


exposed  lines,  E  F  and  E  G  be  unequal,     C  D 

the  proportion  which  E  F  has  to  E  G,  EG  F 
and  that  which  E  G  has  to  E  F  are  also 
exposed  in  them;  for  not  only  the  lines  themselves, 
but  also  their  difference,  G  F,  is  exposed.  The  propor- 
tion of  unequals  is  quantity;  for  the  difference,  G  F, 
in  which  it  consists,  is  quantity.  But  the  proportion 
of  equality  is  not  quantity;  because,  between  equals, 
there  is  no  difference ;  nor  is  one  equality  greater 
than  another,  as  one  inequality  is  greater  than  another 
inequality. 

9.     The  proportion  of  two  times,  or  of  two  uniform 
velocities,  is  then  exposed,   when   two   lines  are  ex- 
posed by  which  two  bodies  are  understood  to  be  moved 
uniformly;   and  therefore  the  same   two   lines   serve 
to   exhibit   both   their   own   proportion,   and   that   of 
the  times  and  velocities,  according  as  they  are  con- 
sidered to  be  exposed  for  the  magnitudes  themselves, 
or  for  the  times  or  velocities.     For  let  the  two 
lines  A  and  B  be  exposed;  their  proportion        A 
therefore  (by  the  last  foregoing  article)  is  ex-        B 
posed ;  and  if  they  be  considered  as  drawn  with 
equal  and  uniform  velocity,  then,  seeing  their  times 
are  greater,  or  equal,  or  less,  according  as  the  same 
spaces  are   transmitted  in  greater,  or  equal,  or  less 
time,  the  lines  A  and  B  will  exhibit  the  equality  or 
inequality,  that  is,  the  proportion   of  the  times.     To 
conclude,  if  the  same  lines,  A  and  B,  be  considered 


92  CONCERNING  BODY. 

as  drawn  in  the  same  time,  then,  seeing  their  veloci- 
ties are  greater,  or  equal,  or  less,  according  as  they 
pass  over  in  the  same  time  longer  or  equal,  or  shorter 
lines,  the  same  lines,  A  and  B,  will  exhibit  the  equality, 
or  inequality,  that  is,  the  proportion  of  their  veloci- 
ties. 

CHAPTER  XIII. 

OF  ANALOGISM,  OR  THE  SAME  PROPORTION. 

I,  2,  3,  4.  The  nature  and  definition  of  proportion,  arithmet- 
ical and  geometrical. — 5.  The  definition,  and  some  proper- 
ties of  the  same  arithmetical  proportion. — 6,  7.  The  defini- 
tion and  transmutations  of  analogism,  or  the  same 
geometrical  proportion. — 8,  9.  The  definitions  of  hyper- 
logism  and  hypologism,  that  is,  of  greater  and  less  propor- 
tion, and  their  transmutations. — 10,  11,  12.  Comparison  of 
analogical  quantities,  according  to  magnitude. — 13,  14,  15. 
Composition  of  proportions. — 16,  17,  18,  19,  20,  21,  22,  23,  24, 

25.  The  definition  and  properties  of  continual  proportion. — 

26,  27,  28,  29.  Comparison  of  arithmetical  and  geometrical 
proportions. 

CHAPTER  XIV. 

OF   STRAIT     AND    CROOKED,    ANGLE    AND    FIGURE. 

I.  The  definition  and  properties  of  a  strait  line. — 2.  The 
definition  and  properties  of  a  plane  superficies. — 3.  Several 
sorts  of  crooked  lines. — 4.  The  definition  and  properties  of 
a  circular  line. — 5.  The  properties  of  a  strait  line  taken  in  a 
plane. — 6.  The  definition  of  tangent  lines. — 7.  The  definition 
of  an  angle,  and  the  kinds  thereof. — 8.  In  concentric  circles, 
arches  of  the  same  angle  are  to  one  another,  as  the  whole 
circumferences  are. — 9.  The  quantity  of  an  angle,  in  what  it 
consists. — 10.  The  distinction  of  angles,  simply  so  called. — 


OF  QUANTITY.  93 

ii.  Of  strait  lines  from  the  centre  of  a  circle  to  a  tangent  of 
the  same. — 12.  The  general  definition  of  parallels,  and  the 
properties  of  strait  parallels. — 13.  The  circumferences  of 
circles  are  to  one  another,  as  their  diameters  are. — 14.  In 
triangles,  strait  lines  parallel  to  the  bases  are  to  one  another, 
as  the  parts  of  the  sides  which  they  cut  off  from  the  vertex. 
— 15.  By  what  fraction  of  a  strait  line  the  circumference  of  a 
circle  is  made.— 16.  That  an  angle  of  contingence  is  quan- 
tity, but  of  a  different  kind  from  that  of  an  angle  simply  so 
called;  and  that  it  can  neither  add  nor  take  way  any  thing 
from  the  same. — 17.  That  the  inclination  of  planes  is  angle 
simply  so  called. — 18.  A  solid  angle,  what  it  is. — 19.  What 
is  the  nature  of  asymptotes. — 20.  Situation,  by  what  it  is 
determined.— 21.  What  is  like  situation;  what  is  figure;  and 
what  are  like  figures. 


PART  III. 

PROPORTIONS  OF    MOTIONS  AND 
MAGNITUDES. 

CHAPTER  XV. 

OF  THE    NATURE,    PROPERTIES,   AND   DIVERS    CONSIDERA- 
TIONS OF  MOTION  AND  ENDEAVOUR. 

I.  Repetition  of  some  principles  of  the  doctrine  of  motion 
formerly  set  down. — 2.  Other  principles  added  to  them. — 
3.  Certain  theorems  concerning  the  nature  of  motion. — 4. 
Divers  considerations  of  motion. — 5.  The  way  by  which  the 
first  endeavour  of  bodies  moved  tendeth. — 6.  In  motion 
which  is  made  by  concourse,  one  of  the  movents  ceasing, 
the  endeavour  is  made  by  the  way  by  which  the  rest  tend. — 
7.  All  endeavour  is  propagated  in  infinitum. — 8.  How  much 
greater  the  velocity  or  magnitude  is  of  a  movent,  so  much 
the  greater  is  the  efficacy  thereof  upon  any  other  body  in  its 
way. 

I.  The  next  things  in  order  to  be  treated  of  are 
motion  and  magnitude,  which  are  the  most  common 
accidents  of  all  bodies.  This  place  therefore  most  prop- 
erly belongs  to  the  elements  of  geometry.  But  because 
this  part  of  philosophy,  having  been  improved  by  the 
best  wits  of  all  ages,  has  afforded  greater  plenty  of 
matter  than  can  well  be  thrust  together  within  the  nar- 
row limits  of  this  discourse,  I  thought  fit  to  admonish 
the  reader,  that  before  he  proceeded  further,  he  take 

95 


96  CONCERNING  BODY. 

into  his  hands  the  works  of  Euclid,  Archimedes,  Apollo- 
nius,  and  other  as  well  ancient  as  modern  writers.  For 
to  what  end  is  it,  to  do  over  again  that  which  is  already 
done?  The  little  therefore  that  I  shall  say  concerning 
geometry  in  some  of  the  following  chapters,  shall  be 
such  only  as  is  new,  and  conducing  to  natural  phi- 
losophy. 

I  have  already  delivered  some  of  the  principles  of 
this  doctrine  in  the  eighth  and  ninth  chapters ;  which  I 
shall  briefly  put  together  here,  that  the  reader  in  going 
on  may  have  their  light  nearer  at  hand. 

First,  therefore,  in  chap,  viii,  art.  10,  motion  is  de- 
fined to  be  the  continual  privation  of  one  place,  and 
acquisition  of  another. 

Secondly,  it  is  there  shown,  that  whatsoever  is  moved 
is  moved  in  time. 

Thirdly,  in  the  same  chapter,  art.  1 1,  I  have  defined 
rest  to  be  when  a  body  remains  for  some  time  in  one 
place. 

Fourthly,  it  is  there  shown,  that  whatsoever  is  moved 
is  not  in  any  determined  place;  as  also  that  the  same 
has  been  moved,  is  still  moved,  and  will  yet  be  moved; 
so  that  in  every  part  of  that  space,  in  which  motion  is 
made,  we  may  consider  three  times,  namely,  the  past, 
the  present,  and  the  future  time. 

Fifthly,  in  art.  15  of  the  same  chapter,  I  have  defined 
velocity  or  swiftness  to  be  motion  considered  as  pozver, 
namely,  that  power  by  which  a  body  moved  may  in  a 
certain  time  transmit  a  certain  length ;  which  also  may 
more  briefly  be  enunciated  thus,  velocity  is  the  quantity 
of  motion  determined  by  time  and  line. 

Sixthly,  in  the  same  chapter,  art.  16,  I  have  shown 
that  motion  is  the  measure  of  time. 

Seventhly,  in  the  same  chapter,  art.  17,  I  have  defined 


MOTION  AND  ENDEAVOUR.  97 

motions  to  be  equally  swift,  when  in  equal  times  equal 
lengths  are  transmitted  by  them. 

Eighthly,  in  art.  1 8  of  the  same  chapter,  motions  are 
defined  to  be  equal,  when  the  swiftness  of  one  moved 
body,  computed  in  every  part  of  its  magnitude,  is  equal 
to  the  swiftness  of  another,  computed  also  in  every  part 
of  its  magnitude.  From  whence  it  is  to  be  noted,  that 
motions  equal  to  one  another,  and  motions  equally 
swift,  do  not  signify  the  same  thing;  for  when  two 
horses  draw  abreast,  the  motion  of  both  is  greater  than 
the  motion  of  either  of  them  singly ;  but  the  swiftness 
of  both  together  is  but  equal  to  that  of  either. 

Ninthly,  in  art.  19  of  the  same  chapter,  I  have  shown, 
that  whatsoever  is  at  rest  will  always  be  at  rest,  unless 
there  be  some  other  body  besides  it,  which  by  getting 
into  its  place  suffers  it  no  longer  to  remain  at  rest. 
And  that  whatsoever  is  moved,  will  always  be  moved, 
unless  there  be  some  other  body  besides  it,  which 
hinders  its  motion. 

Tenthly,  in  chap,  ix,  art.  7,  I  have  demonstrated 
that  when  any  body  is  moved  which  was  formerly  at 
rest,  the  immediate  efficient  cause  of  that  motion  is  in 
some  other  moved  and  contiguous  body. 

Eleventhly,  I  have  shown  in  the  same  place,  that 
whatsoever  is  moved,  will  always  be  moved  in  the 
same  way,  and  with  the  same  swiftness,  if  it  be  not 
hindered  by  some  other  moved  and  contiguous  body. 

2.  To  which  principles  I  shall  here  add  those  that 
follow.  First,  I  define  endeavour  to  be  motion  made 
in  less  space  and  time  than  can  be  given;  that  is  less 
than  can  be  determined  or  assigned  by  exposition  or 
number;  that  is,  motion  made  through  the  length  of  a 
point,  and  in  an  instant  or  point  of  time.  For  the  ex- 
plaining of  which  definition  it  must  be  remembered, 


98  CONCERNING  BODY. 

that  by  a  point  is  not  to  be  understood  that  which  has 
no  quantity,  or  which  cannot  by  any  means  be  divided ; 
for  there  is  no  such  thing  in  nature;  but  that,  whose 
quantity  is  not  at  all  considered,  that  is,  whereof  neither 
quantity  nor  any  part  is  computed  in  demonstration; 
so  that  a  point  is  not  to  be  taken  for  an  indivisible,  but 
for  an  undivided  thing ;  as  also  an  instant  is  to  be  taken 
for  an  undivided,  and  not  for  an  indivisible  time. 

In  like  manner,  endeavour  is  to  be  conceived  as  mo- 
tion ;  but  so  as  that  neither  the  quantity  of  the  time  in 
which,  nor  of  the  line  in  which  it  is  made,  may  in 
demonstration  be  at  all  brought  into  comparison  with 
the  quantity  of  that  time,  or  of  that  line  of  which  it  is 
a  part.  And  yet,  as  a  point  may  be  compared  with  a 
point,  so  one  endeavour  may  be  compared  with  another 
endeavour,  and  one  may  be  found  to  be  greater  or  less 
than  another.  For  if  the  vertical  points  of  two  angles 
be  compared,  they  will  be  equal  or  unequal  in  the  same 
proportion  which  the  angles  themselves  have  to  one 
another.  Or  if  a  strait  line  cut  many  circumferences  of 
concentric  circles,  the  inequality  of  the  points  of  inter- 
section will  be  in  the  same  proportion  which  the  peri- 
meters have  to  one  another.  And  in  the  same  manner, 
if  two  motions  begin  and  end  both  together,  their  en- 
deavours will  be  equal  or  unequal,  according  to  the 
proportion  of  their  velocities ;  as  we  see  a  bullet  of  lead 
descend  with  greater  endeavour  than  a  ball  of  wool. 

Secondly,  I  define  impetus,  or  quickness  of  motion, 
to  be  the  swiftness  or  velocity  of  the  body  moved,  but 
considered  in  the  several  points  of  that  time  in  which 
it  is  moved.  In  which  sense  impetus  is  nothing  else 
but  the  quantity  or  velocity  of  endeavour.  But  con- 
sidered with  the  whole  time,  it  is  the  whole  velocity  of 
the  body  moved  taken  together  throughout  all  the  time, 


MOTION  AND  ENDEAVOUR.  99 

and  equal  to  the  product  of  a  line  representing  the 
time,  multiplied  into  a  line  representing  the  arithmet- 
ically mean  impetus  or  quickness.  Which  arithmet- 
ical mean,  what  it  is,  is  defined  in  the  29th  article  of 
chapter  xiii. 

And  because  in  equal  times  the  ways  that  are  passed 
are  as  the  velocities,  and  the  impetus  is  the  velocity 
they  go  withal,  reckoned  in  all  the  several  points  of  the 
times,  it  followeth  that  during  any  time  whatsoever, 
howsoever  the  impetus  be  increased  or  decreased,  the 
length  of  the  way  passed  over  shall  be  increased  or 
decreased  in  the  same  proportion ;  and  the  same  line 
shall  represent  both  the  way  of  the  body  moved,  and 
the  several  impetus  or  degrees  of  swiftness  wherewith 
the  way  is  passed  over. 

And  if  the  body  moved  be  not  a  point,  but  a  strait 
line  moved  so  as  that  every  point  thereof  make  a 
several  strait  line,  the  plane  described  by  its  motion, 
whether  uniform,  accelerated,  or  retarded,  shall  be 
greater  or  less,  the  time  being  the  same,  in  the  same 
proportion  with  that  of  the  impetus  reckoned  in  one 
motion  to  the  impetus  reckoned  in  the  other.  For  the 
reason  is  the  same  in  parallelograms  and  their  sides. 

Thirdly,  I  define  resistance  to  be  the  endeavour  of 
one  moved  body  either  wholly  or  in  part  contrary  to 
the  endeavour  of  another  moved  body,  which  toucheth 
the  same.  I  say,  wholly  contrary,  when  the  endeavour 
of  two  bodies  proceeds  in  the  same  strait  line  from  the 
opposite  extremes,  and  contrary  in  part,  when  two 
bodies  have  their  endeavour  in  two  lines,  which,  pro- 
ceeding from  the  extreme  points  of  a  strait  line,  meet 
without  the  same. 

Fourthly,  that  I  may  define  what  it  is  to  press,  I  say, 


ioo  CONCERNING  BODY. 

that  of  two  moved  bodies  one  presses  the  other,  when 
with  its  endeavour  it  makes  either  all  or  part  of  the 
other  body  to  go  out  of  its  place. 

Fifthly,  a  body  which  is  pressed  and  not  wholly 
removed,  is  said  to  restore  itself,  when,  the  pressing 
body  being  taken  away,  the  parts  which  were  moved  do, 
by  reason  of  the  internal  constitution  of  the  pressed 
body,  return  every  one  into  its  own  place.  And  this 
we  may  observe  in  springs,  in  blown  bladders,  and  in 
many  other  bodies,  whose  parts  yield  more  or  less  to  the 
endeavour  which  the  pressing  body  makes  at  the  first 
arrival ;  but  afterwards,  when  the  pressing  body  is  re- 
moved, they  do,  by  some  force  within  them,  restore 
themselves,  and  give  their  whole  body  the  same  figure 
it  had  before. 

Sixthly,  I  define  force  to  be  the  impetus  or  quickness 
of  motion  multiplied  either  into  itself,  or  into  the  mag- 
nitude of  the  movent,  by  means  whereof  the  said 
movent  works  more  or  less  upon  the  body  that  re- 
sists it. 

3.  Having  premised  thus  much,  I  shall  now  demon- 
strate, first,  that  if  a  point  moved  come  to  touch  another 
point  which  is  at  rest,  how  little  soever  the  impetus  or 
quickness  of  its  motion  be,  it  shall  move  that  other 
point.  For  if  by  that  impetus  it  do  not  at  all  move  it 
out  of  its  place,  neither  shall  it  move  it  with  double  the 
same  impetus.  For  nothing  doubled  is  still  nothing; 
and  for  the  same  reason  it  shall  never  move  it  with  that 
impetus,  how  many  times  soever  it  be  multiplied,  be- 
cause nothing,  however  it  be  multiplied,  will  for  ever 
be  nothing.  Wherefore,  when  a  point  is  at  rest,  if  it  do 
not  yield  to  the  least  impetus,  it  will  yield  to  none ;  and 
consequently  it  will  be  impossible  that  that,  which  is  at 
rest,  should  ever  be  moved. 


MOTION  AND  ENDEAVOUR.  101 

Secondly,  that  when  a  point  moved,  how  little  soever 
the  impetus  thereof  be,  falls  upon  a  point  of  any  body 
at  rest,  how  hard  soever  that  body  be,  it  will  at  the  first 
touch  make  it  yield  a  little.  For  if  it  do  not  yield  to  the 
impetus  which  is  in  that  point,  neither  will  it  yield  to 
the  impetus  of  never  so  many  points,  which  have  all 
their  impetus  severally  equal  to  the  impetus  of  that 
point.  For  seeing  all  those  points  together  work 
equally,  if  any  one  of  them  have  no  effect,  the  aggre- 
gate of  them  all  together  shall  have  no  effect  as  many 
times  told  as  there  are  points  in  the  whole  body,  that  is, 
still  no  effect  at  all;  and  by  consequent  there  would 
be  some  bodies  so  hard  that  it  would  be  impossible  to 
break  them ;  that  is,  a  finite  hardness,  or  a  finite  force, 
would  not  yield  to  that  which  is  infinite;  which  is 
absurd. 

Coroll.  It  is  therefore  manifest,  that  rest  does  noth- 
ing at  all,  nor  is  of  any  efficacy ;  and  that  nothing  but 
motion  gives  motion  to  such  things  as  be  at  rest,  and 
takes  it  from  things  moved. 

Thirdly,  that  cessation  in  the  movent  does  not 
cause  cessation  in  that  which  was  moved  by  it.  For 
(by  number  n  of  art.  I  of  this  chapter)  whatsoever  is 
moved  perseveres  in  the  same  way  and  with  the  same 
swiftness,  as  long  as  it  is  not  hindered  by  something 
that  is  moved  against  it.  Now  it  is  manifest,  that  cessa- 
tion is  not  contrary  motion ;  and  therefore  it  follows 
that  the  standing  still  of  the  movent  does  not  make  it 
necessary  that  the  thing  moved  should  also  stand  still. 

Coroll.  They  are  therefore  deceived,  that  reckon  the 
taking  away  of  the  impediment  or  resistance  for  one 
of  the  causes  of  motion. 

4.  Motion  is  brought  into  account  for  divers  re- 
spects ;  first,  as  in  a  body  undivided,  that  is,  considered 


102  CONCERNING  BODY. 

as  a  point ;  or,  as  in  a  divided  body.  In  an  undivided 
body,  when  we  suppose  the  way,  by  which  the  motion 
is  made,  to  be  a  line ;  and  in  a  divided  body,  when  we 
compute  the  motion  of  the  several  parts  of  that  body, 
as  of  parts. 

Secondly,  from  the  diversity  of  the  regulation  of 
motion,  it  is  in  body,  considered  as  undivided,  some- 
times uniform  and  sometimes  multiform.  Uniform 
is  that  by  which  equal  lines  are  always  transmitted  in 
equal  times ;  and  multiform,  when  in  one  time  more,  in 
another  time  less  space  is  transmitted.  Again,  of  multi- 
form motions,  there  are  some  in  which  the  degrees  of 
acceleration  and  retardation  proceed  in  the  same 
proportions,  which  the  spaces  transmitted  have,  whether 
duplicate,  or  triplicate,  or  by  whatsoever  number  mul- 
tiplied ;  and  others  in  which  it  is  otherwise. 

Thirdly,  from  the  number  of  the  movents;  that  is, 
one  motion  is  made  by  one  movent  only,  and  another 
by  the  concourse  of  many  movents. 

Fourthly,  from  the  position  of  that  line  in  which  a 
body  is  moved,  in  respect  of  some  other  line ;  and  from 
hence  one  motion  is  called  perpendicular,  another  ob- 
lique, another  [parallel. 

Fifthly,  from  the  position  of  the  movent  in  re- 
spect of  the  moved  body ;  from  whence  one  motion  is 
pulsion  or  driving,  another  traction  or  drawing.  Pul- 
sion, when  the  movent  makes  the  moved  body  go  be- 
fore it;  and  traction,  when  it  makes  it  follow.  Again 
there  are  two  sorts  of  pulsion;  one,  when  the  motions 
of  the  movent  and  moved  body  begin  both  together, 
which  may  be  called  the  trusion  or  thrusting  and  vec- 
tion;  the  other,  when  the  movent  is  first  moved,  and 
afterwards  the  moved  body,  which  motion  is  called 
percussion  or  stroke. 


MOTION  AND  ENDEAVOUR.  103 

Sixthly,  motion  is  considered  sometimes  from  the 
effect  only  which  the  movent  works  in  the  moved 
body,  which  is  usually  called  moment.  Now  moment 
is  the  excess  of  motion  which  the  movent  has  above 
the  motion  or  endeavour  of  the  resisting  body. 

Seventhly,  it  may  be  considered  from  the  diversity 
of  the  medium;  as  one  motion  may  be  made  in  vacuity 
or  empty  place;  another  in  a  fluid;  another  in  a  con- 
sistent medium,  that  is,  a  medium  whose  parts  are  by 
some  power  so  consistent  and  cohering,  that  no  part 
of  the  same  will  yield  to  the  movent,  unless  the  whole 
yield  also. 

Eighthly,  when  a  moved  body  is  considered  as  having 
parts,  there  arises  another  distinction  of  motion  into 
simple  and  compound.  Simple,  when  all  the  several 
parts  describe  several  equal  lines ;  compounded,  when 
the  lines  described  are  unequal. 

5.  All  endeavour  tends  towards  that  part,  that  is 
to  say,  in  that  way  which  is  determined  by  the  motion 
of  the  movent,  if  the  movent  be  but  one;  or,  if  there 
be  many  movents,  in  that  way  which  their  concourse 
determines.  For  example,  if  a  moved  body  have  direct 
motion,  its  first  endeavour  will  be  in  a  strait  line ;  if  it 
have  circular  motion,  its  first  endeavour  will  be  in  the 
circumference  of  a  circle. 

6.  And  whatsoever  the  line  be,  in  which  a  body  has 
its  motion  from  the  concourse  of  two  movents,  as  soon 
as  in  any  point  thereof  the  force  of  one  of  the  movents 
ceases,  there  immediately  the  former  endeavour  of  that 
body  will  be  changed  into  an  endeavour  in  the  line  of 
the  other  movent. 

Wherefore,  when  any  body  is  carried  on  by  the  con- 
course of  two  winds,  one  of  those  winds  ceasing,  the 
endeavour  and  motion  of  that  body  will  be  in  that  line, 


104  CONCERNING  BODY. 

in  which  it  would  have  been  carried  by  that  wind  alone 
which  blows  still.  And  in  the  describing  of  a  circle, 
where  that  which  is  moved  has  its  motion  determined 
by  a  movent  in  a  tangent,  and  by  the  radius  which 
keeps  it  in  a  certain  distance  from  the  centre,  if  the 
retention  of  the  radius  cease,  that  endeavour,  which  was 
in  the  circumference  of  the  circle,  will  now  be  in  the 
tangent,  that  is,  in  a  strait  line.  For,  seeing  endeavour 
is  computed  in  a  less  part  of  the  circumference  than  can 
be  given,  that  is,  in  a  point,  the  way  by  which  a  body 
is  moved  in  the  circumference  is  compounded  of  in- 
numerable strait  lines,  of  which  every  one  is  less  than 
can  be  given ;  which  are  therefore  called  points.  Where- 
fore when  any  body,  which  is  moved  in  the  circum- 
ference of  a  circle,  is  freed  from  the  retention  of  the 
radius,  it  will  proceed  in  one  of  those  strait  lines,  that 
is,  in  a  tangent. 

7.  All  endeavour,  whether  strong  or  weak,  is  propa-. 
gated  to  infinite  distance ;  for  it  is  motion.  If  therefore 
the  first  endeavour  of  a  body  be  made  in  space  which 
is  empty,  it  will  always  proceed  with  the  same  velocity ; 
for  it  cannot  be  supposed  that  it  can  receive  any  re- 
sistance at  all  from  empty  space ;  and  therefore,  (by  art. 
7,  chap,  ix )  will  always  proceed  in  the  same  way  and 
with  the  same  swiftness.  And  if  its  endeavour  be  in 
space  which  is  filled,  yet,  seeing  endeavour  is  mo- 
tion, that  which  stands  next  in  its  way  shall  be  removed, 
and  endeavour  further,  and  again  remove  that  which 
stands  next,  and  so  infinitely.  Wherefore  the  propa- 
gation of  endeavour,  from  one  part  of  full  space  to 
another,  proceeds  infinitely.  Besides,  it  reaches  in  any 
instant  to  any  distance,  how  great  soever.  For  in  the 
same  instant  in  which  the  first  part  of  the  full  medium 
removes  that  which  is  next  it,  the  second  also  removes 


MOTION  AND  ENDEAVOUR.  105 

that  part  which  is  next  to  it ;  and  therefore  all  endeav- 
our, whether  it  be  in  empty  or  in  full  space,  proceeds 
not  only  to  any  distance,  how  great  soever,  but  also  in 
any  time,  how  little  soever,  that  is,  in  an  instant.  Nor 
makes  it  any  matter,  that  endeavour,  by  proceeding, 
grows  weaker  and  weaker,  till  at  last  it  can  no  longer 
be  perceived  by  sense;  for  motion  may  be  insensible; 
and  I  do  not  here  examine  things  by  sense  and  experi- 
ence, but  by  reason. 

8.  When  two  movents  are  of  equal  magnitude, 
the  swifter  of  them  works  with  greater  force  than  the 
slower,  upon  a  body  that  resists  their  motion.  Also, 
if  two  movents  have  equal  velocity,  the  greater  of 
them  works  with  more  force  than  the  less.  For  where 
the  magnitude  is  equal,  the  movent  of  greater  ve- 
locity makes  the  greater  impression  upon  that  body 
upon  which  it  falls;  and  where  the  velocity  is  equal, 
the  movent  of  greater  magnitude  falling  upon  the 
same  point,  or  an  equal  part  of  another  body,  loses  less 
of  its  velocity,  because  the  resisting  body  works  only 
upon  that  part  of  the  movent  which  it  touches,  and 
therefore  abates  the  impetus  of  that  part  only ;  whereas 
in  the  mean  time  the  parts,  which  are  not  touched,  pro- 
ceed, and  retain  their  whole  force,  till  they  also  come 
to  be  touched ;  and  their  force  has  some  effect.  Where- 
fore, for  example,  in  batteries  a  longer  than  a  shorter 
piece  of  timber  of  the  same  thickness  and  velocitcy,  and 
a  thicker  than  a  slenderer  piece  of  the  same  length  and 
velocity,  work  a  greater  effect  upon  the  wall. 


106  CONCERNING  BODY. 

CHAPTER  XVI. 

OF    MOTION    ACCELERATED   AND    UNIFORM,    AND   OF 
MOTION    BY   CONCOURSE. 

I.  The  velocity  of  any  body,  in  what  time  soever  it  be  com- 
puted, is  that  which  is  made  of  the  multiplication  of  the 
impetus,  or  quickness  of  its  motion  into  the  time. — 2-5.  In 
all  motion,  the  lengths  which  are  passed  through  are  to  one 
another,  as  the  products  made  by  the  impetus  multiplied  into 
the  time. — 6.  If  two  bodies  be  moved  with  uniform  motion 
through  two  lengths,  the  proportion  of  those  lengths  to  one 
another  will  be  compounded  of  the  proportions  of  time  to 
time,  and  impetus  to  impetus,  directly  taken. — 7.  If  two 
bodies  pass  through  two  lengths  with  uniform  motion,  the 
proportion  of  their  time  to  one  another  will  be  compounded 
of  the  proportions  of  length  to  length,  and  impetus  to  impe- 
tus reciprocally  taken ;  also  the  proportion  of  their  impetus 
to  one  another  will  be  compounded  of  the  proportions  of 
length  to  length,  and  time  to  time  reciprocally  taken. — 8.  If 
a  body  be  carried  on  with  uniform  motion  by  two  movents 
together,  which  meet  in  an  angle,  the  line  by  which  it  passes 
will  be  a  strait  line,  subtending  the  complement  of  that 
angle  to  two  right  angles. — 9,  &c.  If  a  body  be  carried  by 
two  movents  together,  one  of  them  being  moved  with  uni- 
form, the  other  with  accelerated  motion,  and  the  proportion 
of  their  lengths  to  their  times  being  explicable  in  numbers, 
how  to  find  out  what  line  that  body  describes. 

CHAPTER  XVII. 

OF    FIGURES   DEFICIENT. 

1.  Definitions  of  a  deficient  figure;  of  a  complete  figure;  of  the 
complement  of  a  deficient  figure;  and  of  proportions  which 
are  proportional  and  commensurable  to  one  another. — 2.  The 
proportion  of  a  deficient  figure  to  its  complement. — 3.  The 
proportions    of   deficient    figures    to    the    parallelograms    in 


CONCERNING  BODY.  107 

which  they  are  described,  set  forth  in  a  table. — 4.  The  de- 
scription and  production  of  the  same  figures. — 5.  The  draw- 
ing of  tangents  to  them. — 6.  In  what  proportion  the  same 
figures  exceed  a  strait-lined  triangle  of  the  same  altitude 
and  base. — 7.  A  table  of  solid  deficient  figures  described  in 
a  cylinder. — 8.  In  what  proportion  the  same  figures  exceed 
a  cone  of  the  same  altitude  and  base. — 9.  How  a  plain  defi- 
cient figure  may  be  described  in  a  parallelogram,  so  that  it 
be  to  a  triangle  of  the  same  base  and  altitude,  as  another 
deficient  figure,  plain  or  solid,  twice  taken,  is  to  the  same 
deficient  figure,  together  with  the  complete  figure  in  which  it 
is  described. — 10.  The  transferring  of  certain  properties  of 
deficient  figures  described  in  a  parallelogram  to  the  propor- 
tions of  the  spaces  transmitted  with  several  degrees  of  veloc- 
ity.— 11.  Of  deficient  figures  described  in  a  circle. — 12.  The 
proposition  demonstrated  in  art.  2  confirmed  from  the  ele- 
ments of  philosophy. — 13.  An  unusual  way  of  reasoning 
concerning  the  equality  between  the  superficies  of  a  portion 
of  a  sphere  and  a  circle. — 14.  How  from  the  description  of 
deficient  figures  in  a  parallelogram,  any  number  of  mean 
proportionals  may  be  found  out  between  two  given  strait 
lines. 

CHAPTER  XVIII. 

OF  THE  EQUATION  OF  STRAIT  LINES  WITH  THE 
CROOKED  LINES  OF  PARABOLAS  AND  OTHER  FIGURES 
MADE  IN  IMITATION  OF  PARABOLAS. 

i.  To  find  the  strait  line  equal  to  the  crooked  line  of  a  semi- 
parabola. — 2.  To  find  a  strait  line  equal  to  the  crooked  line  of 
the  first  semiparabolaster,  or  to  the  crooked  line  of  any  other 
of  the  deficient  figures  of  the  table  of  the  3d  article  of  the 
precedent  chapter. 


108  CONCERNING  BODY. 

CHAPTER  XIX. 

OF    ANGLES     OF     INCIDENCE    AND    REFLECTION,     EQUAL 
BY   SUPPOSITION. 

I.  If  two  strait  lines  falling  upon  another  strait  line  be  parallel, 
the  lines  reflected  from  them  shall  also  be  parallel.— 2.  If 
two  strait  lines  drawn  from  one  point  fall  upon  another 
strait  line,  the  lines  reflected  from  them,  if  they  be  drawn  out 
the  other  way,  will  meet  in  an  angle  equal  to  the  angle  made 
by  the  lines  of  incidence.— 3.  If  two  strait  parallel  lines, 
drawn  not  oppositely,  but  from  the  same  parts,  fall  upon  the 
circumference  of  a  circle,  the  lines  reflected  from  them,  if 
produced  they  meet  within  the  circle,  will  make  an  angle 
double  to  that  which  is  made  by  two  strait  lines  drawn  from 
the  centre  to  the  points  of  incidence. — 4.  If  two  strait  lines 
drawn  from  the  same  point  without  a  circle  fall  upon  the 
circumference,  and  the  lines  reflected  from  them  being  pro- 
duced meet  within  the  circle,  they  will  make  an  angle  equal 
to  twice  that  angle,  which  is  made  by  two  strait  lines  drawn 
from  the  centre  to  the  points  of  incidence,  together  with  the 
angle  which  the  incident  lines  themselves  make. — 5.  If  two 
strait  lines  drawn  from  one  point  fall  upon  the  concave  cir- 
cumference of  a  circle,  and  the  angle  they  make  be  less  than 
twice  the  angle  at  the  centre,  the  lines  reflected  from  them  and 
meeting  within  the  circle  will  make  an  angle,  which  being 
added  to  the  angle  of  the  incident  lines  will  be  equal  to 
twice  the  angle  at  the  centre.— 6.  If  through  any  one  point 
two  unequal  chords  be  drawn  cutting  one  another,  and  the 
centre  of  the  circle  be  not  placed  between  them,  and  the 
lines  reflected  from  them  concur  wheresoever,  there  cannot 
through  the  point,  through  which  the  two  former  lines  were 
drawn,  be  drawn  any  other  strait  line  whose  reflected  line 
shall  pass  through  the  common  point  of  the  two  former 
lines  reflected. — 7.  In  equal  chords  the  same  is  not  true. — 
8.  Two  points  being  given  in  the  circumference  of  a  circle,  to 
draw  two  strait  lines  to  them,  so  that  their  reflected  lines 
may  contain  any  angle  given.— 9.  If  a  strait  line  falling  upon 

the  circumference   of  a  circle  be  produced  till  it  reach  the 


CONCERNING  BODY.  109 

semidiameter,  and  that  part  of  it,  which  is  intercepted  be- 
tween the  circumference  and  the  semidiameter,  be  equal  to 
that  part  of  the  semidiameter  which  is  between  the  point  of 
concourse  and  the  centre,  the  reflected  line  will  be  parallel 
to  the  semidiameter. — 10.  If  from  a  point  within  a  circle, 
two  strait  lines  be  drawn  to  the  circumference,  and  their 
reflected  lines  meet  in  the  circumference  of  the  same  circle, 
the  angle  made  by  the  reflected  lines  will  be  a  third  part  of 
the  angle  made  by  the  incident  lines. 

CHAPTER  XX. 


OF    THE    DIMENSION    OF    A    CIRCLE,    AND    THE    DIVISION 
OF   ANGLES   OR   ARCHES. 

I.  The  dimension  of  a  circle  never  determined  in  numbers  by 
Archimedes  and  others. — 2.  The  first  attempt  for  the  finding 
out  of  the  dimension  of  a  circle  by  lines. — 3.  The  second 
attempt  for  the  finding  out  of  the  dimension  of  a  circle  from 
the  consideration  of  the  nature  of  crookedness. — 4.  The  third 
attempt ;  and  some  things  propounded  to  be  further  searched 
into. — 5.  The  equation  of  the  spiral  of  Archimedes  with  a 
strait  line. — 6.  Of  the  analysis  of  geometricians  by  the  pow- 
ers of  lines. 

CHAPTER  XXL 

OF   CIRCULAR    MOTION. 

I.  In  simple  motion,  every  strait  line  taken  in  the  body  moved 
is  so  carried,  that  it  is  always  parallel  to  the  places  in  which 
it  formerly  was. — 2.  If  circular  motion  be  made  about  a  rest- 
ing centre,  and  in  that  circle  there  be  an  epicycle,  whose 
revolution  is  made  the  contrary  way,  in  such  manner  that  in 
equal  times  it  make  equal  angles,  every  strait  line  taken  in 
that  epicycle  will  be  so  carried,  that  it  will  always  be  par- 
allel to  the  places  in  which  it  formerly  was. — 3.  The  prop- 
erties of  simple  motion. — 4.  If  a  fluid  be  moved  with  simple 


no  CONCERNING  BODY. 

circular  motion,  all  the  points  taken  in  it  will  describe  their 
circles  in  times  proportional  to  the  distances  from  the  cen- 
tre.—5.  Simple  motion  dissipates  heterogeneous  and  con- 
gregates homogeneous  bodies. — 6.  If  a  circle  made  by  a 
movent  moved  with  simple  motion  be  commensurable  to 
another  circle  made  by  a  point  which  is  carried  about  by 
the  same  movent,  all  the  points  of  both  the  circles  will  at 
some  time  return  to  the  same  situation. — 7.  If  a  sphere  have 
simple  motion,  its  motion  will  more  dissipate  heterogeneous 
bodies  by  how  much  it  is  more  remote  from  the  poles.— 8. 
If  the  simple  circular  motion  of  a  fluid  body  be  hindered  by 
a  body  which  is  not  fluid,  the  fluid  body  will  spread  itself 
upon  the  superficies  of  that  body.— 9.  Circular  motion  about 
a  fixed  centre  casteth  off  by  the  tangent  such  things  as  lie 
upon  the  circumference  and  stick  not  to  it.— 10.  Such  things, 
as  are  moved  with  simple  circular  motion,  beget  simple  cir- 
cular motion. — 11.  If  that  which  is  so  moved  have  one  side 
hard  and  the  other  side  fluid,  its  motion  will  not  be  per- 
fectly circular. 

CHAPTER  XXII. 


OF  OTHER   VARIETY   OF   MOTION. 

I.  Endeavour  and  pressure  how  they  differ.— 2.  Two  kinds  of 
mediums  in  which  bodies  are  moved.— 3.  Propagation  of 
motion,  what  it  is.— 4.  What  motion  bodies  have,  when  they 
press  one  another.— 5.  Fluid  bodies,  when  they  are  pressed 
together,  penetrate  one  another.— 6.  When  one  body  presseth 
another  and  doth  not  penetrate  it,  the  action  of  the  pressing 
body  is  perpendicular  to  the  superficies  of  the  body  pressed.— 
7-  When  a  hard  body,  pressing  another  body,  penetrates  the 
same,  it  doth  not  penetrate  it  perpendicularly,  unless  it  fall 
perpendicularly  upon  it.— 8.  Motion  sometimes  opposite  to 
that  of  the  movent.— 9.  In  a  full  medium,  motion  is  propa- 
gated to  any  distance.— 10.  Dilatation  and  contraction  what 
they  are.— 11.  Dilatation  and  contraction  suppose  mutation 
of  the  smallest  parts  in  respect  of  their  situation.— 12.  All 
traction  is  pulsion.— 13.  Such  things  as  being  pressed  or 
bent  restore  themselves,  have  motion  in  their  internal  parts.— 


CONCERNING  BODY.  in 

14.  Though  that  which  carrieth  another  be  stopped,  the  body 
carried  will  proceed. — 15,  16.  The  effects  of  percussion  not 
to  be  compared  with  those  of  weight. — 17,  18.  Motion  can- 
not begin  first  in  the  internal  parts  of  the  body. — 19.  Action 
and  reaction  proceed  in  the  same  line. — 20.  Habit,  what  it  is. 

CHAPTER  XXIII. 

OF     THE     CENTRE     OF     EQUIPONDERATION  J     OF     BODIES 
PRESSING  DOWNWARDS   IN   STRAIT  PARALLEL  LINES. 

I.  Definitions  and  suppositions. — 2.  Two  planes  of  equiponder- 
ation  are  not  parallel. — 3.  The  centre  of  equiponderation  is 
in  every  plane  of  equiponderation. — 4.  The  moments  of  equal 
ponderants  are  to  one  another  as  their  distances  from  the 
centre  of  the  scale. — 5,  6..  The  moments  of  unequal  ponder- 
ants have  their  proportion  to  one  another  compounded 
of  the  proportions  of  their  weights  and  distances  from  the 
centre  of  the  scale. — 7.  If  two  ponderants  have  their  weights 
and  distances  from  the  centre  of  the  scale  in  reciprocal  pro- 
portion, they  are  equally  poised ;  and  contrarily. — 8.  If  the 
parts  of  any  ponderant  press  the  beams  of  the  scale  every- 
where equally,  all  the  parts  cut  off,  reckoned  from  the  cen- 
tre of  the  scale,  will  have  their  moments  in  the  same  pro- 
portion with  that  of  the  parts  of  a  triangle  cut  off  from  the 
vertex  by  strait  lines  parallel  to  the  base. — 9.  The  diameter 
of  equiponderation  of  figures,  which  are  deficient  according 
to  commensurable  proportions  of  their  altitudes  and  bases, 
divides  the  axis,  so  that  the  part  taken  next  the  vertex  is  to 
the  other  part  of  the  complete  figure  to  the  deficient  figure. — 
10.  The  diameter  of  equiponderation  of  the  complement  of 
the  half  of  any  of  the  said  deficient  figures,  divides  that  line 
which  is  drawn  through  the  vertex  parallel  to  the  base,  so 
that  the  part  next  the  vertex  is  to  the  other  part  of  the  com- 
plete figure  to  the  complement. — n.  The  centre  of  equi- 
ponderation of  the  half  of  any  of  the  deficient  figures  in  the 
first  row  of  the  table  of  art.  3,  chap,  xvii,  may  be  found  out 
by  the  numbers  of  the  second  row. — 12.  The  centre  of  equi- 
ponderation of  the  half  of  any  of  the  figures  of  the  second 


H2  CONCERNING  BODY. 

row  of  the  same  table,  may  be  found  out  by  the  numbers  of 
the  fourth  row.— 13.  The  centre  of  equiponderation  of  the 
half  of  any  of  the  figures  in  the  same  table  being  known,  the 
centre  of  the  excess  of  the  same  figure  above  a  triangle  of 
the  same  altitude  and  base  is  also  known.— 14.  The  centre  of 
equiponderation  of  a  solid  sector  is  in  the  axis  so  divided, 
that  the  part  next  the  vertex  be  to  the  whole  axis,  wanting 
half  the  axis  of  the  portion  of  the  sphere,  as  3  to  4. 

CHAPTER  XXIV. 

OF   REFRACTION   AND   REFLECTION. 

I.  Definitions. — 2.  In  perpendicular  motion  there  is  no  refrac- 
tion.—3.  Things  thrown  out  of  a  thinner  into  a  thicker  me- 
dium are  so  refracted  that  the  angle  refracted  is  greater  than 
the  angle  of  inclination. — 4.  Endeavour,  which  from  one 
point  tendeth  every  way,  will  be  so  refracted,  as  that  the 
sine  of  the  angle  refracted  will  be  to  the  sine  of  the  angle  of 
inclination,   as  the  density  of  the  first  medium   is  to  the 

-  density  of  the  second  medium,  reciprocally  taken. — 5.  The 
sine  of  the  refracted  angle  in  one  inclination  is  to  the  sine 
of  the  refracted  angle  in  another  inclination,  as  the  sine  of 
the  angle  of  that  inclination  is  to  the  sine  of  the  angle  of 
this  inclination. — 6.  If  two  lines  of  incidence,  having  equal 
inclination,  be  the  one  in  a  thinner,  the  other  in  a  thicker 
medium,  the  sine  of  the  angle  of  inclination  will  be  a  mean 
proportional  between  the  two  sines  of  the  refracted  angles. — 

7.  If  the  angle  of  inclination  be  semirect,  and  the  line  of  in- 
clination be  in  the  thicker  medium,  and  the  proportion  of 
their  densities  be  the  same  with  that  of  the  diagonal  to  the 
side  of  a  square,  and  the  separating  superficies  be  plane, 
the    refracted   line   will   be   in   the   separating   superficies. — 

8.  If  a  body  be  carried  in  a  strait  line  upon  another  body, 
and  do  not  penetrate  the  same,  but  be  reflected  from  it,  the 
angle  of  reflection  will  be  equal  to  the  angle  of  incidence. — 

9.  The  same  happens  in  the  generation  of  motion  in  the  line 
of  incidence. 


PART  IV. 

PHYSICS,  OR  THE  PHENOMENA 
OF  NATURE. 

CHAPTER  XXV.* 

OF    SENSE   AND    ANIMAL    MOTION. 

I.  The  connexion  of  what  hath  been  said  with  that  which  fol- 
loweth. — 2.  The  investigation  of  the  nature  of  sense,  and  the 
definition  of  sense. — 3.  The  subject  and  object  of  sense.— 
4.  The  organs  of  sense. — 5.  All  bodies  are  not  indued  with 
sense. — 6.  But  one  phantasm  at  one  and  the  same  time. — 
7.  Imagination  the  remains  of  past  sense,  which  also  is 
memory.  Of  sleep. — 8.  How  phantasms  succeed  one  an- 
other.— 9.  Dreams,  whence  they  proceed. — 10.  Of  the  senses, 
their  kinds,  their  organs,  and  phantasms  proper  and  com- 
mon.— 11.  The  magnitude  of  images,  how  and  by  what  it  is 
determined. — 12.  Pleasure,  pain,  appetite  and  aversion,  what 
they  are. — 13.  Deliberation  and  will,  what. 

i.  I  have,  in  the  first  chapter,  defined  philosophy 
to  be  knowledge  of  effects  acquired  by  true  ratiocination, 
from  knozvledge  first  had  of  their  causes  and  gen- 
cration;  and  of  such  causes  or  generations  as  may  be, 
from  former  knowledge  of  their  effects  or  appear- 
ances. There  are,  therefore,  two  methods  of  philoso- 
phy; one,  from  the  generation  of  things  to  their 
possible  effects ;  and  the  other,  from  their  effects  or  ap- 


*  For  list  of  the  writings  of  Hobbes  on  psychology,  cf.  p.  xx. 
113 


ii4  CONCERNING  BODY. 

pearances  to  some  possible  generation  of  the  same.  In 
the  former  of  these  the  truth  of  the  first  principles  of 
our  ratiocination,  namely  definitions,  is  made  and  con- 
stituted by  ourselves,  whilst  we  consent  and  agree 
about  the  appellations  of  things.  And  this  part  I  have 
finished  in  the  foregoing  chapters;  in  which,  if  I  am 
not  deceived,  I  have  affirmed  nothing,  saving  the  defi- 
nitions themselves,  which  hath  not  good  coherence 
with  the  definitions  I  have  given ;  that  is  to  say,  which 
is  not  sufficiently  demonstrated  to  all  those,  that  agree 
with  me  in  the  use  of  words  and  appellations ;  for  whose 
sake  only  I  have  written  the  same.  I  now  enter  upon 
the  other  part ;  which  is  the  finding  out  by  the  appear- 
ances or  effects  of  nature,  which  we  know  by  sense, 
some  ways  and  means  by  which  they  may  be,  I  do  not 
say  they  are,  generated.  The  principles,  therefore, 
upon  which  the  following  discourse  depends,  are  not 
such  as  we  ourselves  make  and  pronounce  in  general 
terms,  as  definitions ;  but  such,  as  being  placed  in  the 
things  themselves  by  the  Author  of  Nature,  are  by  us 
observed  in  them ;  and  we  make  use  of  them  in  single 
and  particular,  not  universal  propositions.  Nor  do 
they  impose  upon  us  any  necessity  of  constituting 
theorems ;  their  use  being  only,  though  not  without  such 
general  propositions  as  have  been  already  demonstrated, 
to  show  us  the  possibility  of  some  production  or  gen- 
eration. Seeing,  therefore,  the  science,  which  is  here 
taught,  hath  its  principles  in  the  appearances  of  nature, 
and  endeth  in  the  attaining  of  some  knowledge  of 
natural  causes,  I  have  given  to  this  part  the  title  of 
Physics,  or  the  Phenomena  of  Nature.  Now  such 
things  as  appear,  or  are  shown  to  us  by  nature,  we  call 
phenomena  or  appearances. 

Of  all   the  phenomena  or   appearances   which   are 


OF  SENSE  AND  ANIMAL  MOTION.  115 

near  us,  the  most  admirable  is  apparition  itself, 
to  cjxiLveo-Ocu ;  namely,  that  some  natural  bodies  have 
in  themselves  the  patterns  almost  of  all  things,  and 
others  of  none  at  all.  So  that  if  the  appearances  be 
the  principles  by  which  we  know  all  other  things, 
we  must  needs  acknowledge  sense  to  be  the  principle 
by  which  we  know  those  principles,  and  that  all  the 
knowledge  we  have  is  derived  from  it.  And  as  for 
the  causes  of  sense,  we  cannot  begin  our  search  of 
them  from  any  other  phenomenon  than  that  of  sense 
itself.  But  you  will  say,  by  what  sense  shall  we  take 
notice  of  sense?  I  answer,  by  sense  itself,  namely,  by 
the  memory  which  for  some  time  remains  in  us  of 
things  sensible,  though  they  themselves  pass  away.  For 
he  that  perceives  that  he  hath  perceived,  remembers. 

In  the  first  place,  therefore,  the  causes  of  our  per- 
ception, that  is,  the  causes  of  those  ideas  and  phan- 
tasms which  are  perpetually  generated  within  us  whilst 
we  make  use  of  our  senses,  are  to  be  enquired  into; 
and  in  what  manner  their  generation  proceeds.  To 
help  which  inquisition,  we  may  observe  first  of  all,  that 
our  phantasms  or  ideas  are  not  always  the  same;  but 
that  new  ones  appear  to  us,  and  old  ones  vanish,  ac- 
cording as  we  apply  our  organs  of  sense,  now  to  one 
object,  now  to  another.  Wherefore  they  are  generated, 
and  perish.  And  from  hence  it  is  manifest,  that  they 
are  some  change  or  mutation  in  the  sentient. 

2.  Now  that  all  mutation  or  alteration  is  motion 
or  endeavour  (and  endeavour  also  is  motion)  in  the 
internal  parts  of  the  thing  that  is  altered,  hath  been 
proved  (in  art.  9,  chap,  viii)  from  this,  that  whilst 
even  the  least  parts  of  any  body  remain  in  the  same 
situation  in  respect  of  one  another,  it  cannot  be  said 
that  any  alteration,  unless  perhaps  that  the  whole  body 


n6  CONCERNING  BODY. 

together  hath  been  moved,  hath  happened  to  it ;  but  that 
it  both  appeareth  and  is  the  same  it  appeared  and  was 
before.  Sense,  therefore,  in  the  sentient,  can  be  noth- 
ing else  but  motion  in  some  of  the  internal  parts  of 
the  sentient;  and  the  parts  so  moved  are  parts  of  the 
organs  of  sense.  For  the  parts  of  our  body,  by  which 
we  perceive  any  thing,  are  those  we  commonly  call  the 
organs  of  sense.  And  so  we  find  what  is  the  subject  of 
our  sense,  namely,  that  in  which  are  the  phantasms; 
and  partly  also  we  have  discovered  the  nature  of  sense, 
namely,  that  it  is  some  internal  motion  in  the  sentient. 

I  have  shown  besides  (in  chap,  ix,  art.  7)  that  no 
motion  is  generated  but  by  a  body  contiguous  and 
moved :  from  whence  it  is  manifest,  that  the  immediate 
cause  of  sense  or  perception  consists  in  this,  that  the 
first  organ  of  sense  is  touched  and  pressed.  For  when 
the  uttermost  part  of  the  organ  is  pressed,  it  no  sooner 
yields,  but  the  part  next  within  it  is  pressed  also ;  and, 
in  this  manner,  the  pressure  or  motion  is  propagated 
through  all  the  parts  of  the  organ  to  the  innermost. 
And  thus  also  the  pressure  of  the  uttermost  part  pro- 
ceeds from  the  pressure  of  some  more  remote  body,  and 
so  continually,  till  we  come  to  that  from  which,  as 
from  its  fountain,  we  derive  the  phantasm  or  idea  that 
is  made  in  us  by  our  sense.  And  this,  whatsoever  it 
be,  is  that  we  commonly  call  the  object.  Sense,  there- 
fore, is  some  internal  motion  in  the  sentient,  generated 
by  some  internal  motion  of  the  parts  of  the  object,  and 
propagated  through  all  the  media  to  the  innermost  part 
of  the  organ.  By  which  words  I  have  almost  defined 
what  sense  is. 

Moreover,  I  have  shown  (art.  2,  chap,  xv)  that  all 
resistance  is  endeavour  opposite  to  another  endeavour, 
that  is  to  say,  reaction.     Seeing,  therefore,  there  is  in 


OF  SENSE  AND  ANIMAL  MOTION.  117 

the  whole  organ,  by  reason  of  it  own  internal  natural 
motion,  some  resistance  or  reaction  against  the  motion 
which  is  propagated  from  the  object  to  the  innermost 
part  of  the  organ,  there  is  also  in  the  same  organ  an 
endeavour  opposite  to  the  endeavour  which  proceeds 
from  the  object;  so  that  when  that  endeavour  inwards 
is  the  last  action  in  the  act  of  sense,  then  from  the  re- 
action, how  little  soever  the  duration  of  it  be,  a  phan- 
tasm or  idea  hath  its  being ;  which,  by  reason  that  the 
endeavour  is  now  outwards,  doth  always  appear  as 
something  situate  without  the  organ.  So  that  now  I 
shall  give  you  the  whole  definition  of  sense,  as  it  is 
drawn  from  the  explication  of  the  causes  thereof  and 
the  order  of  its  generation,  thus :  sense  is  a  phantasm, 
made  by  the  reaction  and  endeavour  outwards  in  the 
organ  of  sense,  caused  by  an  endeavour  inwards  from 
the  object,  remaining  for  some  time  more  or  less. 

3.  The  subject  of  sense  is  the  sentient  itself,  namely, 
some  living  creature ;  and  we  speak  more  correctly, 
when  we  say  a  living  creature  seeth,  than  when  we 
say  the  eye  seeth.  The  object  is  the  thing  received; 
and  it  is  more  accurately  said,  that  we  see  the  sun, 
than  that  we  see  the  light.  For  light  and  colour,  and 
heat  and  sound,  and  other  qualities  which  are  common- 
ly called  sensible,  are  not  objects,  but  phantasms  in  the 
sentients.  For  a  phantasm  is  the  act  of  sense,  and  dif- 
fers no  otherwise  from  sense  than  fieri,  that  is,  being  a 
doing,  differs  from  factum  esse,  that  is,  being  done; 
which  difference,  in  things  that  are  done  in  an  instant, 
is  none  at  all;  and  a  phantasm  is  made  in  an  instant. 
For  in  all  motion  which  proceeds  by  perpetual  propa- 
gation, the  first  part  being  moved  moves  the  second, 
the  second  the  third,  and  so  on  to  the  last,  and  that 
to   any   distance,   how   great   soever.     And   in    what 


n8  CONCERNING  BODY. 

point  of  time  the  first  or  foremost  part  proceeded  to 
the  place  of  the  second,  which  is  thrust  on,  in  the  same 
point  of  time  the  last  save  one  proceeded  into 
the  place  of  the  last  yielding  part;  which  by  reaction, 
in  the  same  instant,  if  the  reaction  be  strong  enough, 
makes  a  phantasm;  and  a  phantasm  being  made,  per- 
ception is  made  together  with  it. 

4.  The  organs  of  sense,  which  are  in  the  sentient, 
are  such  parts  thereof,  that  if  they  be  hurt,  the  very 
generation  of  phantasms  is  thereby  destroyed,  though 
all  the  rest  of  the  parts  remain  entire.  Now  these  parts 
in  the  most  of  living  creatures  are  found  to  be  certain 
spirits  and  membranes,  which,  proceeding  from  the 
pia  mater,  involve  the  brain  and  all  the  nerves ;  also  the 
brain  itself,  and  the  arteries  which  are  in  the  brain; 
and  such  other  parts,  as  being  stirred,  the  heart  also, 
which  is  the  fountain  of  all  sense,  is  stirred  together 
with  them.  For  whensoever  the  action  of  the  object 
reacheth  the  body  of  the  sentient,  that  action  is  by 
some  nerve  propagated  to  the  brain ;  and  if  the  nerve 
leading  thither  be  so  hurt  or  obstructed,  that  the  motion 
can  be  propagated  no  further,  no  sense  follows.  Also 
if  the  motion  be  intercepted  between  the  brain  and  the 
heart  by  the  defect  of  the  organ  by  which  the  action  is 
proagated,  there  will  be  no  perception  of  the  object. 

5.  But  though  all  sense,  as  I  have  said,  be  made  by 
reaction,  nevertheless  it  is  not  necessary  that  every  thing 
that  reacteth  should  have  sense.  I  know  there  have 
been  philosophers,  and  those  learned  men,  who  have 
maintained  that  all  bodies  are  endued  with  sense.  Nor 
do  I  see  how  they  can  be  refuted,  if  the  nature  of  sense 
be  placed  in  reaction  only.  And,  though  by  the  reac- 
tion of  bodies  inanimate  a  phantasm  might  be  made,  it 
would  nevertheless  cease,  as  soon  as  ever  the  object 


OF  SENSE  AND  ANIMAL  MOTION.  119 

were  removed.  For  unless  those  bodies  had  organs,  as 
living  creatures  have,  fit  for  the  retaining  of  such  mo- 
tion as  is  made  in  them,  their  sense  would  be  such,  as 
that  they  should  never  remember  the  same.  And 
therefore  this  hath  nothing  to  do  with  that  sense  which 
is  the  subject  of  my  discourse.  For  by  sense,  we  com- 
monly understand  the  judgment  we  make  of  objects  by 
their  phantasms;  namely,  by  comparing  and  distin- 
guishing those  phantasms ;  which  we  could  never  do,  if 
that  motion  in  the  organ,  by  which  the  phantasm  is 
made,  did  not  remain  there  for  some  time,  and  make 
the  same  phantasm  return.  Wherefore  sense,  as  I  here 
understand  it,  and  which  is  commonly  so  called,  hath 
necessarily  some  memory  adhering  to  it,  by  which 
former  and  later  phantasms  may  be  compared  together, 
and  distinguished  from  one  another. 

Sense,  therefore,  properly  so  called,  must  necessarily 
have  in  it  a  perpetual  variety  of  phantasms,  that  they 
may  be  discerned  one  from  another.  For  if  we  should 
suppose  a  man  to  be  made  with  clear  eyes,  and  all  the 
rest  of  his  organs  of  sight  well  disposed,  but  endued 
with  no  other  sense ;  and  that  he  should  look  only  upon 
one  thing,  which  is  always  of  the  same  colour  and 
figure,  without  the  least  appearance  of  variety,  he  would 
seem  to  me,  whatsoever  others  may  say,  to  see,  no  more 
than  I  seem  to  myself  to  feel  the  bones  of  my  own 
limbs  by  my  organs  of  feeling ;  and  yet  those  bones  are 
always  and  on  all  sides  touched  by  a  most  sensible 
membrane.  I  might  perhaps  say  he  were  astonished, 
and  looked  upon  it ;  but  I  should  not  say  he  saw  it ; 
it  being  almost  all  one  for  a  man  to  be  always  sensible 
of  one  and  the  same  thing,  and  not  to  be  sensible  at  all 
of  any  thing. 

6.     And  yet  such  is  the  nature  of  sense,  that  it  does 


120  CONCERNING  BODY. 

not  permit  a  man  to  discern  many  things  at  once.  For 
seeing  the  nature  of  sense  consists  in  motion ;  as  long 
as  the  organs  are  employed  about  one  object,  they 
cannot  be  so  moved  by  another  at  the  same  time,  as  to 
make  by  both  their  motions  one  sincere  phantasm  of 
each  of  them  at  once.  And  therefore  two  several 
phantasms  will  not  be  made  by  two  objects  working 
together,  but  only  one  phantasm  compounded  from  the 
action  of  both. 

Besides,  as  when  we  divide  a  body,  we  divide  its 
place;  and  when  we  reckon  many  bodies,  we  must 
necessarily  reckon  as  many  places ;  and  contrarily,  as 
I  have  shown  in  the  seventh  chapter ;  so  what  number 
soever  we  say  there  be  at  times,  we  must  understand 
the  same  number  of  motions  also;  and  as  oft  as  we 
count  many  motions,  so  oft  we  reckon  many  times. 
For  though  the  object  we  look  upon  be  of  divers 
colours,  yet  with  those  divers  colours  it  is  but  one 
varied  object,  and  not  variety  of  objects. 

Moreover,  whilst  those  organs  which  are  common 
to  all  the  senses,  such  as  are  those  parts  of  every  organ 
which  proceed  in  men  from  the  root  of  the  nerves  to  the 
heart,  are  vehemently  stirred  by  a  strong  action  from 
some  one  object,  they  are,  by  reason  of  the  contumacy 
which  the  motion,  they  have  already,  gives  them  against 
the  reception  of  all  other  motion,  made  the  less  fit  to 
receive  any  other  impression  from  whatsoever  other 
objects,  to  what  sense  soever  those  objects  belong. 
And  hence  it  is,  that  an  earnest  studying  of  one  object, 
takes  away  the  sense  of  all  other  objects  for  the 
present.  For  study  is  nothing  else  but  a  possession  of 
the  mind,  that  is  to  say,  a  vehement  motion  made  by 
some  one  object  in  the  organs  of  sense,  which  are 
stupid  to  all  other  motions  as  long  as  this  lasteth ;  ac- 


OF  SENSE  AND  ANIMAL  MOTION.  121 

cording  to  what  was  said  by  Terence,  ''  Populus  studio 
stupidus  in  funambulo  animum  occuparat."  For  what 
is  stupor  but  that  which  the  Greeks  called  draio-tf^cria, 
that,  is,  a  cessation  from  the  sense  of  other  things? 
Wherefore  at  one  and  the  same  time,  we  cannot  by 
sense  perceive  more  than  one  single  object;  as  in  read- 
ing, we  see  the  letters  successively  one  by  one,  and  not 
all  together,  though  the  whole  page  be  presented  to  our 
eye ;  and  though  every  several  letter  be  distinctly  writ- 
ten there,  yet  when  we  look  upon  the  whole  page  at 
once,  we  read  nothing. 

From  hence  it  is  manifest,  that  every  endeavour  of 
the  organ  outwards,  is  not  to  be  called  sense,  but  that 
only,  which  at  several  times  is  by  vehemence  made 
stronger  and  more  predominate  than  the  rest;  which 
deprives  us  of  the  sense  of  other  phantasms,  no  other- 
wise than  the  sun  deprives  the  rest  of  the  stars  of  light 
not  by  hindering  their  action,  but  by  obscuring  and 
hiding  them  with  his  excess  of  brightness. 

7.  But  the  motion  of  the  organ,  by  which  a  phan- 
tasm is  made,  is  not  commonly  called  sense,  except  the 
object  be  present.  And  the  phantasm  remaining  after 
the  object  is  removed  or  past  by,  is  called  fancy,  and 
in  Latin  imaginatio;  which  word,  because  all  phantasms 
are  not  images,  doth  not  fully  answer  the  signification 
of  the  word  fancy  in  its  general  acceptation.  Never- 
theless I  may  use  it  safely  enough,  by  understanding 
it  for  the  Greek  ^avracrui. 

Imagination  therefore  is  nothing  else  but  sense  de- 
caying, or  weakened,  by  the  absence  of  the  object.  But 
what  may  be  the  cause  of  this  decay  or  weakening? 
Is  the  motion  the  weaker,  because  the  object  is  taken 
away?  If  it  were,  then  phantasms  would  always  and 
necessarily  be  less  clear  in  the  imagination,  than  they 


122  CONCERNING  BODY. 

are  in  sense ;  which  is  not  true.  For  in  dreams,  which 
are  the  imaginations  of  those  that  sleep,  they  are  no 
less  clear  than  in  sense  itself.  But  the  reason  why  in 
men  waking  the  phantasms  of  things  past  are  more 
obscure  than  those  of  things  present,  is  this,  that  their 
organs  being  at  the  same  time  moved  by  other  present 
objects,  those  phantasms  are  the  less  predominate. 
Whereas  in  sleep,  the  passages  being  shut  up,  external 
action  doth  not  at  all  disturb  or  hinder  internal  motion. 

If  this  be  true,  the  next  thing  to  be  considered,  will 
be,  whether  any  cause  may  be  found  out,  from  the  sup- 
position whereof  it  will  follow,  that  the  passage  is  shut 
up  from  the  external  objects  of  sense  to  the  internal 
organ.  I  suppose,  therefore,  that  by  the  continual  ac- 
tion of  objects,  to  which  a  reaction  of  the  organ,  and 
more  especially  of  the  spirits,  is  necessarily  consequent, 
the  organ  is  wearied,  that  is,  its  parts  are  no  longer 
moved  by  the  spirits  without  some  pain;  and  conse- 
quently the  nerves  being  abandoned  and  grown  slack, 
they  retire  to  their  fountain,  which  is  the  cavity  either 
of  the  brain  or  of  the  heart ;  by  which  means  the  action 
which  proceeded  by  the  nerves  is  necessarily  inter- 
cepted. For  action  upon  a  patient,  that  retires  from  it, 
makes  but  little  impression  at  the  first;  and  at  last, 
when  the  nerves  are  by  little  and  little  slackened,  none 
at  all.  And  therefore  there  is  no  more  reaction,  that  is, 
no  more  sense,  till  the  organ  being  refreshed  by  rest, 
and  by  a  supply  of  new  spirits  recovering  strength  and 
motion,  the  sentient  awaketh.  And  thus  it  seems  to  be 
always,  unless  some  other  preternatural  cause  inter- 
vene; as  heat  in  the  internal  parts  from  lassitude,  or 
from  some  disease  stirring  the  spirits  and  other  parts 
of  the  organ  in  some  extraordinary  manner. 

8.     Now  it  is  not  without  cause,  nor  so  casual  a 


OF  SENSE  AND  ANIMAL  MOTION.  123 

thing  as  many  perhaps  think  it,  that  phantasms  in  this 
their  great  variety  proceed  from  one  another ;  and  that 
the  same  phantasms  sometimes  bring  into  the  mind 
other  phantasms  like  themselves,  and  at  other  times 
extremely  unlike.  For  in  the  motion  of  any  continued 
body,  one  part  follows  another  by  cohesion ;  and  there- 
fore, whilst  we  turn  our  eyes  and  other  organs  succes- 
sively to  many  objects,  the  motion  which  was  made  by 
every  one  of  them  remaining,  the  phantasms  are  re- 
newed as  often  as  any  one  of  those  motions  comes  to 
be  predominant  above  the  rest;  and  they  become  pre- 
dominant in  the  same  order  in  which  at  any  time 
formerly  they  were  generated  by  sense.  So  that  when 
by  length  of  time  very  many  phantasms  have  been  gen- 
erated within  us  by  sense,  then  almost  any  thought  may 
arise  from  any  other  thought;  insomuch  that  it  may 
seem  to  be  a  thing  indifferent  and  casual,  which  thought 
shall  follow  which.  But  for  the  most  part  this  is  not 
so  uncertain  a  thing  to  waking  as  to  sleeping  men.  For 
the  thought  or  phantasm  of  the  desired  end  brings 
in  all  the  phantasms,  that  are  means  conducing  to  that 
end,  and  that  in  order  backwards  from  the  last  to  the 
first,  and  again  forwards  from  the  beginning  to  the 
end.  But  this  supposes  both  appetite,  and  judgment  to 
discern  what  means  conduce  to  the  end,  which  is  gotten 
by  experience;  and  experience  is  store  of  phantasms, 
arising  from  the  sense  of  very  many  things.  For 
<j>avTd£e<rOat,  and  memhiisse,  fancy  and  memory,  differ 
only  in  this,  that  memory  supposeth  the  time  past, 
which  fancy  doth  not.  In  memory,  the  phantasms  we 
consider  are  as  if  they  were  worn  out  with  time;  but 
in  our  fancy  we  consider  them  as  they  are ;  which  dis- 
tinction is  not  of  the  things  themselves,  but  of  the  con- 
siderations of  the  sentient.     For  there  is  in  memory 


124  CONCERNING  BODY. 

something  like  that  which  happens  in  looking  upon 
things  at  a  great  distance ;  in  which  as  the  small  parts 
of  the  object  are  not  discerned,  by  reason  of  their 
remoteness;  so  in  memory,  many  accidents  and  places 
and  parts  of  things,  which  were  formerly  perceived  by 
sense,  are  by  length  of  time  decayed  and  lost. 

The  perpetual  arising  of  phantasms,  both  in  sense 
and  imagination,  is  that  which  we  commonly  call  dis- 
course of  the  mind,  and  is  common  to  men  with  other 
living  creatures.  For  he  that  thinketh,  compareth  the 
phantasms  that  pass,  that  is,  taketh  notice  of  their  like- 
ness or  unlikeness,  to  one  another.  And  as  he  that  ob- 
serves readily  the  likenesses  of  things  of  different  na- 
tures, or  that  are  very  remote  from  one  another,  is  said 
to  have  a  good  fancy ;  so  he  is  said  to  have  a  good  judg- 
ment, that  finds  out  the  unlikenesses  or  differences  of 
things  that  are  like  one  another.  Now  this  observation 
of  differences  is  not  perception  made  by  a  common 
organ  of  sense,  distinct  from  sense  or  perception  prop- 
erly so  called,  but  is  memory  of  the  differences  of  par- 
ticular phantasms  remaining  for  some  time;  as  the 
distinction  between  hot  and  lucid,  is  nothing  else  but 
the  memory  both  of  a  heating,  and  of  an  enlightening 
object. 

9.  The  phantasms  of  men  that  sleep,  are  dreams. 
Concerning  which  we  are  taught  by  experience  these 
five  things.  First,  that  for  the  most  part  there  is  neither 
order  nor  coherence  in  them.  Secondly,  that  we  dream 
of  nothing  but  what  is  compounded  and  made  up  of 
the  phantasms  of  sense  past.  Thirdly,  that  sometimes 
they  proceed,  as  in  those  that  are  drowsy,  from  the  in- 
terruption of  their  phantasms  by  little  and  little,  broken 
and  altered  through  sleepiness ;  and  sometimes  also 
they  begin  in  the  midst  of  sleep.     Fourthly,  that  they 


OF  SENSE  AND  ANIMAL  MOTION.  125 

are  clearer  than  the  imaginations  of  waking  men,  ex- 
cept such  as  are  made  by  sense  itself,  to  which  they  are 
equal  in  clearness.  Fifthly,  that  when  we  dream,  we 
admire  neither  the  places  nor  the  looks  of  the  things 
that  appear  to  us.  Now  from  what  hath  been  said,  it  is 
not  hard  to  show  what  may  be  the  causes  of  these  phe- 
nomena. For  as  for  the  first,  seeing  all  order  and  co- 
herence proceeds  from  frequent  looking  back  to  the 
end,  that  is,  from  consultation;  it  must  needs  be,  that 
seeing  in  sleep  we  lose  all  thought  of  the  end,  our  phan- 
tasms succeed  one  another,  not  in  that  order  which 
tends  to  any  end,  but  as  it  happeneth,  and  in  such  man- 
ner, as  objects  present  themselves  to  our  eyes  when  we 
look  indifferently  upon  all  things  before  us,  and  see 
them,  not  because  we  would  see  them,  but  because  we 
do  not  shut  our  eyes ;  for  then  they  appear  to  us  with- 
out any  order  at  all.  The  second  proceeds  from  this, 
that  in  the  silence  of  sense  there  is  no  new  motion  from 
the  objects,  and  therefore  no  new  phantasm,  un- 
less we  call  that  new,  which  is  compounded  of  old 
ones,  as  a  chimera,  a  golden  mountain,  and  the  like. 
As  for  the  third,  why  a  dream  is  sometimes  as  it  were 
the  continuation  of  sense,  made  up  of  broken  phan- 
tasms, as  in  men  distempered  with  sickness,  the  reason 
is  manifestly  this,  that  in  some  of  the  organs  sense 
remains,  and  in  others  it  faileth.  But  how  some  phan- 
tasms may  be  revived,  when  all  the  exterior  organs  are 
benumbed  with  sleep,  is  not  so  easily  shown.  Never- 
theless that,  which  hath  already  been  said,  contains  the 
reason  of  this  also.  For  whatsoever  strikes  the  p'ia 
mater,  reviveth  some  of  those  phantasms  that  are  still  in 
motion  in  the  brain ;  and  when  any  internal  motion  of 
the  heart  reacheth  that  membrane,  then  the  predomi- 
nant motion  in  the  brain  makes  the  phantasm.     Now 


126  CONCERNING  BODY. 


the  motions  of  the  heart  are  appetites  and  aversions,  01 
which  I  shall  presently  speak  further.  And  as  appetites 
and  aversions  are  generated  by  phantasms,  so  recip- 
rocally phantasms  are  generated  by  appetites  and 
aversions.  For  example,  heat  in  the  heart  proceeds 
from  anger  and  fighting;  and  again,  from  heat  in  the 
heart,  whatsoever  be  the  cause  of  it,  is  generated  anger 
and  the  image  of  an  enemy,  in  sleep.  And  as  love  and 
beauty  stir  up  heat  in  certain  organs;  so  heat  in  the 
same  organs,  from  whatsoever  it  proceeds,  often 
causeth  desire  and  the  image  of  an  unresisting  beauty. 
Lastly,  cold  doth  in  the  same  manner  generate  fear  in 
those  that  sleep,  and  causeth  them  to  dream  of  ghosts, 
and  to  have  phantasms  of  horror  and  danger;  as  fear 
also  causeth  cold  in  those  that  wake.  So  reciprocal  are 
the  motions  of  the  heart  and  brain.  The  fourth,  namely, 
that  the  things  we  seem  to  see  and  feel  in  sleep,  are  as 
clear  as  in  sense  itself,  proceeds  from  two  causes ;  one, 
that  having  then  no  sense  of  things  without  us,  that 
internal  motion  which  makes  the  phantasm,  in  the  ab- 
sence of  all  other  impressions,  is  predominant ;  and  the 
other,  that  the  parts  of  our  phantasms  which  are  de- 
cayed and  worn  out  by  time,  are  made  up  with  other 
fictitious  parts.  To  conclude,  when  we  dream,  we  do 
not  wonder  at  strange  places  and  the  appearances  of 
things  unknown  to  us,  because  admiration  requires  that 
the  things  appearing  be  new  and  unusual,  which  can 
happen  to  none  but  those  that  remember  former  appear- 
ances ;  whereas  in  sleep,  all  things  appear  as  present. 

But  it  is  here  to  be  observed,  that  certain  dreams, 
especially  such  as  some  men  have  when  they  are  be- 
tween sleeping  and  waking,  and  such  as  happen  to  those 
that  have  no  knowledge  of  the  nature  of  dreams  and 
are  withal  superstitious,  were  not  heretofore  nor  are 


OF  SENSE  AND  ANIMAL  MOTION.  127 

now  accounted  dreams.  For  the  apparitions  men 
thought  they  saw,  and  the  voices  they  thought  they 
heard  in  sleep,  were  not  believed  to  be  phantasms,  but 
things  subsisting  of  themselves,  and  objects  without 
those  that  dreamed.  For  to  some  men,  as  well  sleeping 
as  waking,  but  especially  to  guilty  men,  and  in  the 
night,  and  in  hallowed  places,  fear  alone,  helped  a  little 
with  the  stories  of  such  apparitions,  hath  raised  in  their 
minds  terrible  phantasms,  which  have  been  and  are  still 
deceitfully  received  for  things  really  true,  under  the 
names  of  ghosts  and  incorporeal  substances. 

10.  In  most  living  creatures  there  are  observed  five 
kinds  of  senses,  which  are  distinguished  by  their 
organs,  and  by  their  different  kinds  of  phantasms; 
namely,  sight,  hearing,  smell,  taste,  and  touch;  and 
these  have  their  organs  partly  peculiar  to  each  of  them 
severally,  and  partly  common  to  them  all.  The  organ 
of  sight  is  partly  animate,  and  partly  inanimate.  The 
inanimate  parts  are  the  three  humours ;  namely,  the 
watery  humour,  which  by  the  interposition  of  the  mem- 
brane called  uvea,  the  perforation  whereof  is  called  the 
apple  of  the  eye,  is  contained  on  one  side  by  the  first 
concave  superficies  of  the  eye,  and  on  the  other  side  by 
the  ciliary  processes,  and  the  coat  of  the  crystalline 
humor ;  the  crystalline,  which,  hanging  in  the  midst  be- 
tween the  ciliary  processes,  and  being  almost  of  spher- 
ical figure,  and  of  a  thick  consistence,  is  enclosed  on  all 
sides  with  its  own  transparent  coat ;  and  the  vitreous  or 
glassy  humour,  which  filleth  all  the  rest  of  the  cavity  of 
the  eye,  and  is  somewhat  thicker  than  the  watery 
humour,  but  thinner  than  the  crystalline.  The  animate 
part  of  the  organ  is,  first,  the  membrane  choroeides, 
which  is  a  part  of  the  pia  mater,  saving  that  it  is  cov- 
ered with  a  coat  derived  from  the  marrow  of  the  optic 


128  CONCERNING  BODY. 

nerve,  which  is  called  the  retina;  and  this  choroeides, 
seeing  it  is  part  of  the  pia  mater,  is  continued  to  the 
beginning  of  the  medulla  spinalis  within  the  scull,  in 
which  all  the  nerves  which  are  within  the  head  have 
their  roots.  Wherefore  all  the  animal  spirits  that  the 
nerves  receive,  enter  into  them  there ;  for  it  is  not  imag- 
inable that  they  can  enter  into  them  anywhere  else. 
Seeing  therefore  sense  is  nothing  else  but  the  action  of 
objects  propagated  to  the  furthest  part  of  the  organ; 
and  seeing  also  that  animal  spirits  are  nothing  but 
vital  spirits  purified  by  the  heart,  and  carried  from 
it  by  the  arteries;  it  follows  necessarily,  that  the  ac- 
tion is  derived  from  the  heart  by  some  of  the  arteries 
to  the  roots  of  the  nerves  which  are  in  the  head, 
whether  those  arteries  be  the  plexus  retiformis,  or 
whether  they  be  other  arteries  which  are  inserted 
into  the  substance  of  the  brain.  And,  therefore, 
those  arteries  are  the  complement  or  the  remaining 
part  of  the  whole  organ  of  sight.  And  this  last  part 
is  a  common  organ  to  all  the  senses ;  whereas,  that 
which  reacheth  from  the  eye  to  the  roots  of  the  nerves 
is  proper  only  to  sight.  The  proper  organ  of  hearing 
is  the  tympanum  of  the  ear  and  its  own  nerve;  from 
which  to  the  heart  the  organ  is  common.  So  the  proper 
organs  of  smell  and  taste  are  nervous  membranes,  in 
the  palate  and  tongue  for  the  taste,  and  in  the  nostrils 
for  the  smell ;  and  from  the  roots  of  those  nerves  to  the 
heart  all  is  common.  Lastly,  the  proper  organ  of  touch 
are  nerves  and  membranes  dispersed  through  the  whole 
body;  which  membranes  are  derived  from  the  root  of 
the  nerves.  And  all  things  else  belonging  alike  to  all 
the  senses  seem  to  be  administered  by  the  arteries,  and 
not  by  the  nerves. 

The  proper  phantasm  of  sight  is  light;  and  under 


OF  SENSE  AND  ANIMAL  MOTION.  129 

this  name  of  light,  colour  also,  which  is  nothing  but 
perturbed  light,  is  comprehended.  Wherefore  the 
phantasm  of  a  lucid  body  is  light;  and  of  a  coloured 
body  colour.  But  the  object  of  sight,  properly  so  called, 
is  neither  light  nor  colour,  but  the  body  itself  which  is 
lucid,  or  enlightened,  or  coloured.  For  light  and  colour, 
being  phantasms  of  the  sentient,  cannot  be  accidents  of 
the  object.  Which  is  manifest  enough  from  this,  that 
visible  things  appear  oftentimes  in  places  in  which  we 
know  assuredly  they  are  not,  and  that  in  different  places 
they  are  of  different  colours,  and  may  at  one  and  the 
same  time  appear  in  divers  places.  Motion,  rest,  mag- 
nitude, and  figure,  are  common  both  to  the  sight  and 
touch  ;  and  the  whole  appearance  together  of  figure,  and 
light  or  colour,  is  by  the  Greeks  commonly  called 
cl'Sos,  and  aSwAoi/,  and  ISea;  and  by  the  Latins  species 
and  imago ;  all  which  names  signify  no  more  but 
appearance. 

The  phantasm  which  is  made  by  hearing,  is  sound; 
by  smell,  odour ;  by  taste,  savour ;  and  by  touch,  hard- 
ness and  softness,  heat  and  cold,  wetness,  oiliness,  and 
many  more,  which  are  easier  to  be  distinguished  by 
sense  than  words.  Smoothness,  roughness,  rarity,  and 
density,  refer  to  figure,  and  are  therefore  common  both 
to  touch  and  sight.  And  as  for  the  objects  of  hearing, 
smell,  taste,  and  touch,  they  are  not  sound,  odour, 
savour,  hardness,  &c,  but  the  bodies  themselves  from 
which  sound,  odour,  savour,  hardness,  &c.  proceed ;  of 
the  causes  of  which,  and  of  the  manner  how  they  are 
produced,  I  shall  speak  hereafter. 

But  these  phantasms,  though  they  be  effects  in  the 
sentient,  as  subject,  produced  by  objects  working  upon 
the  organs  ;  yet  there  are  also  other  effects  besides  these, 
produced  by  the  same  objects  in  the  same  organs; 


130  CONCERNING  BODY. 

namely,  certain  motions  proceeding  from  sense,  which 
are  called  animal  motions.  For  seeing  in  all  sense  of 
external  things  there  is  mutual  action  and  reaction,  that 
is,  two  endeavours  opposing  one  another,  it  is  manifest 
that  the  motion  of  both  of  them  together  will  be  con- 
tinued every  way,  especially  to  the  confines  of  both  the 
bodies.  And  when  this  happens  in  the  internal  organ, 
the  endeavour  outwards  will  proceed  in  a  solid  angle, 
which  will  be  greater,  and  consequently  the  idea  great- 
er, than  it  would  have  been  if  the  impression  had  been 
weaker. 

ii.  From  hence  the  natural  cause  is  manifest,  first, 
why  those  things  seem  to  be  greater,  which,  ccuteris 
paribus,  are  seen  in  a  greater  angle :  secondly,  why  in  a 
serene  cold  night,  when  the  moon  doth  not  shine,  more 
of  the  fixed  stars  appear  than  at  another  time.  For 
their  action  is  less  hindered  by  the  serenity  of  the  air, 
and  not  obscured  by  the  greater  light  of  the  moon, 
which  is  then  absent ;  and  the  cold,  making  the  air  more 
pressing,  helpeth  or  strengtheneth  the  action  if  the  stars 
upon  our  eyes ;  in  so  much  as  stars  may  then  be  seen 
which  are  seen  at  no  other  time.  And  this  may  suffice 
to  be  said  in  general  concerning  sense  made  by  the  re- 
action of  the  organ.  For,  as  for  the  place  of  the  image, 
the  deceptions  of  sight,  and  other  things  of  which  we 
have  experience  in  ourselves  by  sense,  seeing  they  de- 
pend for  the  most  part  upon  the  fabric  itself  of  the  eye 
of  man,  I  shall  speak  of  them  then  when  I  come  to 
speak  of  man. 

12.  But  there  is  another  kind  of  sense,  of  which  I 
will  say  something  in  this  place,  namely,  the  sense  of 
pleasure  and  pain,  proceeding  not  from  the  reaction  of 
the  heart  outwards,  but  from  continual  action  from  the 
outermost  part  of  the  organ  towards  the  heart.     For 


OF  SENSE  AND  ANIMAL  MOTION.  131 

the  original  of  life  being  in  the  heart,  that  motion  in 
the  sentient,  which  is  propagated  to  the  heart,  must 
necessarily  make  some  alteration  or  diversion  of  vital 
motion,  namely,  by  quickening  or  slackening,  helping  or 
hindering  the  same.  Now  when  it  helpeth,  it  is  pleas- 
ure ;  and  when  it  hindereth,  it  is  pain,  trouble,  grief,  &c. 
And  as  phantasms  seem  to  be  without,  by  reason  of  the 
endeavour  outwards,  so  pleasure  and  pain,  by  reason 
of  the  endeavour  of  the  organ  inwards,  seem  to  be 
within ;  namely,  there  where  the  first  cause  of  the 
pleasure  or  pain  is ;  as  when  the  pain  proceeds  from  a 
wound,  we  think  the  pain  and  the  wound  are  both  in  the 
same  place. 

Now  vital  motion  is  the  motion  of  the  blood,  per- 
petually circulating  (as  hath  been  shown  from  many 
infallible  signs  and  marks  by  Doctor  Harvey,  the 
first  observer  of  it)  in  the  veins  and  arteries.  Which 
motion,  when  it  is  hindered  by  some  other  motion  made 
by  the  action  of  sensible  objects,  may  be  restored  again 
either  by  bending  or  setting  strait  the  parts  of  the 
body ;  which  is  done  when  the  spirits  are  carried  now 
into  these,  now  into  other  nerves,  till  the  pain,  as  far  as 
is  possible,  be  quite  taken  away.  But  if  vital  motion  be 
helped  by  motion  made  by  sense,  then  the  parts  of  the 
organ  will  be  disposed  to  guide  the  spirits  in  such 
manner  as  conduceth  most  to  the  preservation  and  aug- 
mentation of  that  motion,  by  the  help  of  the  nerves. 
And  in  animal  motion  this  is  the  very  first  endeavour, 
and  found  even  in  the  embryo ;  which  while  it  is  in  the 
womb,  moveth  its  limbs  with  voluntary  motion,  for  the 
avoiding  of  whatsoever  troubleth  it,  or  for  the  pursuing 
of  what  pleaseth  it.  And  this  first  endeavour,  when  it 
tends  towards  such  things  as  are  known  by  experience 
to  be  pleasant,  is  called  appetite,  that  is,  an  approach- 


132  CONCERNING  BODY. 

ing;  and  when  it  shuns  what  is  troublesome,  aversion, 
or  flying  from  it.  And  little  infants,  at  the  beginning 
and  as  soon  as  they  are  born,  have  appetite  to  very  few 
things,  as  also  they  avoid  very  few,  by  reason  of  their 
want  of  experience  and  memory;  and  therefore  they 
have  not  so  great  a  variety  of  animal  motion  as  we  see 
in  those  that  are  more  grown.  For  it  is  not  possible, 
without  such  knowledge  as  is  derived  from  sense,  that 
is,  without  experience  and  memory,  to  know  what  will 
prove  pleasant  or  hurtful ;  only  there  is  some  place  for 
conjecture  from  the  looks  or  aspects  of  things.  And 
hence  it  is,  that  though  they  do  not  know  what  may  do 
them  good  or  harm,  yet  sometimes  they  approach  and 
sometimes  retire  from  the  same  thing,  as  their  doubt 
prompts  them.  But  afterwards,  by  accustoming  them- 
selves by  little  and  little,  they  come  to  know  readily 
what  is  to  be  pursued  and  what  to  be  avoided ;  and  also 
to  have  a  ready  use  of  their  nerves  and  other  organs,  in 
the  pursuing  and  avoiding  of  good  and  bad.  Where- 
fore appetite  and  aversion  are  the  first  endeavours  of 
animal  motion. 

Consequent  to  this  first  endeavour,  is  the  impulsion 
into  the  nerves  and  retraction  again  of  animal  spirits, 
of  which  it  is  necessary  there  be  some  receptacle  or 
place  near  the  original  of  the  nerves ;  and  this  motion 
or  endeavour  is  followed  by  a  swelling  and  relaxation 
of  the  muscles ;  and  lastly,  these  are  followed  by  con- 
traction and  extension  of  the  limbs,  which  is  animal 
motion. 

13.  The  considerations  of  appetites  and  aversions 
are  divers.  For  seeing  living  creatures  have  sometimes 
appetite  and  sometimes  aversion  to  the  same  thing,  as 
they  think  it  will  either  be  for  their  good  or  their  hurt ; 
while  that  vicissitude  of  appetites  and  aversions  remains 


OF  SENSE  AND  ANIMAL  MOTION.  133 

in  them,  they  have  that  series  of  thoughts  which  is 
called  deliberation;  which  lasteth  as  long  as  they  have 
it  in  their  power  to  obtain  that  which  pleaseth,  or  to 
avoid  that  which  displeaseth  them.  Appetite,  therefore, 
and  aversion  are  simply  so  called  as  long  as  they  follow 
not  deliberation.  But  if  deliberation  have  gone  before, 
then  the  last  act  of  it,  if  it  be  appetite,  is  called  will;  if 
aversion,  unwillingness.  So  that  the  same  thing  is 
called  both  will  and  appetite;  but  the  consideration  of 
them,  namely,  before  and  after  deliberation,  is  divers. 
Nor  is  that  which  is  done  within  a  man  whilst  he 
willeth  any  thing,  different  from  that  which  is  done  in 
other  living  creatures,  whilst,  deliberation  having  pre- 
ceded, they  have  appetite. 

Neither  is  the  freedom  of  willing  or  not  willing, 
greater  in  man,  than  in  other  living  creatures.  For 
where  there  is  appetite,  the  entire  cause  of  appetite  hath 
preceded;  and,  consequently,  the  act  of  appetite  could 
not  choose  but  follow,  that  is,  hath  of  necessity  fol- 
lowed (as  is  shown  in  chapter  ix,  article  5).  And 
therefore  such  a  liberty  as  is  free  from  necessity,  is  not 
to  be  found  in  the  will  either  of  men  or  beasts.  But  if 
by  liberty  we  understand  the  faculty  or  power,  not  of 
willing,  but  of  doing  what  they  will,  then  certainly  that 
liberty  is  to  be  allowed  to  both,  and  both  may  equally 
have  it,  whensoever  it  is  to  be  had. 

Again,  when  appetite  and  aversion  do  with  celerity 
succeed  one  another,  the  whole  series  made  by  them 
hath  its  name  sometimes  from  one,  sometimes  from  the 
other.  For  the  same  deliberation,  whilst  it  inclines 
sometimes  to  one,  sometimes  to  the  other,  is  from  ap- 
petite called  hope,  and  from  aversion,  fear.  For  where 
there  is  no  hope,  it  is  not  to  be  called  fear,  but  hate; 
and  where  no  fear,  not  hope,  but  desire.     To  conclude, 


134  CONCERNING  BODY. 

all  the  passions,  called  passions  of  the  mind,  consist  of 
appetite  and  aversion,  except  pure  pleasure  and  pain, 
which  are  a  certain  fruition  of  good  or  evil ;  as  anger 
is  aversion  from  some  imminent  evil,  but  such  as  is 
joined  with  appetite  of  avoiding  that  evil  by  force.  But 
because  the  passions  and  perturbations  of  the  mind  are 
innumerable,  and  many  of  them  not  to  be  discerned  in 
any  creatures  besides  men ;  I  will  speak  of  them  more 
at  large  in  that  section  which  is  concerning  man.  As 
for  those  objects,  if  there  be  any  such,  which  do  not  at 
all  stir  the  mind,  we  are  said  to  contemn  them. 

And  thus  much  of  sense  in  general.     In  the  next 
place  I  shall  speak  of  sensible  objects. 

CHAPTER  XXVI. 

OF  THE   WORLD   AND   OF   THE   STARS. 

I.  The  magnitude  and  duration  of  the  world,  inscrutable. — 2. 
No  place  in  the  world  empty. — 3.  The  arguments  of  Lucre- 
tius for  vacuum,  invalid. — 4.  Other  arguments  for  the  estab- 
lishing of  vacuum,  invalid. — 5.  Six  suppositions  for  the 
solving  of  the  phenomena  of  nature. — 6.  Possible  causes  of 
the  motions  annual  and  diurnal ;  and  of  the  apparent  direc- 
tion, station,  and  retrogradation  of  the  planets. — 7.  The  sup- 
position of  simple  motion,  why  likely. — 8.  The  cause  of  the 
eccentricity  of  the  annual  motion  of  the  earth. — 9.  The 
cause  why  the  moon  hath  always  one  and  the  same  face 
turned  towards  the  earth. — 10.  The  cause  of  the  tides  of  the 
ocean. — 11.  The  cause  of  the  precession  of  the  equinoxes. 

CHAPTER   XXVII. 

OF  LIGHT,   HEAT,  AND  OF  COLOURS. 

I.  Of  the  immense  magnitude  of  some  bodies,  and  the  un- 
speakable littleness  of  others. — 2.  Of  the  cause  of  the  light  of 


OF  LIGHT,  HEAT,  AND  OF  COLOURS.  135 

the  sun. — 3.  How  light  heateth. — 4.  The  generation  of  fire 
from  the  sun. — 5.  The  generation  of  fire  from  collision. 
6.  The  cause  of  light  in  glow-worms,  rotten  wood,  and  the 
Bolognan  stone. — 7.  The  cause  of  light  in  the  concussion  of 
sea  water. — 8.  The  cause  of  flame,  sparks,  and  colliquation. 
9.  The  cause  why  wet  hay  sometimes  burns  of  its  own 
accord ;  also  the  cause  of  lightning. — 10.  The  cause  of  the 
force  of  gunpowder ;  and  what  is  to  be  ascribed  to  the  coals, 
what  to  the  brimstone,  and  what  to  the  nitre. — 11.  How  heat 
is  caused  by  attrition. — 12.  The  distinction  of  light  into  first, 
second,  &c. — 13.  The  causes  of  the  colours  we  see  in  looking 
through  a  prisma  of  glass,  namely,  of  red,  yellow,  blue,  and 
violet  colour. — 14.  Why  the  moon  and  the  stars  appear  red- 
der in  the  horizon  than  in  the  midst  of  the  heaven.— 15.  The 
cause  of  whiteness. — 16.  The  cause  of  blackness. 

I.  Besides  the  stars,  of  which  I  have  spoken  in 
the  last  chapter,  whatsover  other  bodies  there  be  in  the 
world,  they  may  be  all  comprehended  under  the  name 
of  intersidereal  bodies.  And  these  I  have  already  sup- 
posed to  be  either  the  most  fluid  aether,  or  such  bodies 
whose  parts  have  some  degree  of  cohesion.  Now, 
these  differ  from  one  another  in  their  several  consisten- 
cies, magnitudes,  motions,  and  figures.  In  consistency, 
I  suppose  some  bodies  to  be  harder,  others  softer 
through  all  the  several  degrees  of  tenacity.  In  magni- 
tude, some  to  be  greater,  others  less,  and  many  un- 
speakably little.  For  we  must  remember  that,  by  the 
understanding,  quantity  is  divisible  into  divisibles  per- 
petually. And  therefore,  if  a  man  could  do  as  much 
with  his  hands  as  he  can  with  his  understanding,  he 
would  be  able  to  take  from  any  given  magnitude  a  part 
which  should  be  less  than  any  other  magnitude  given. 
But  the  Omnipotent  Creator  of  the  world  can  actually 
from  a  part  of  any  thing  take  another  part,  as  far  as 
we  by  our  understanding  can  conceive  the  same  to  be 


136  CONCERNING  BODY. 

divisible.  Wherefore  there  is  no  impossible  smallness 
of  bodies.  And  what  hinders  but  that  we  may  think 
this  likely?  For  we  know  there  are  some  living  crea- 
tures so  small  that  we  can  scarce  see  their  whole  bodies. 
Yet  even  these  have  their  young  ones ;  their  little  veins 
and  other  vessels,  and  their  eyes  so  small  as  that  no 
microscope  can  make  them  visible.  So  that  we  cannot 
suppose  any  magnitude  so  little,  but  that  our  very  sup- 
position is  actually  exceeded  by  nature.  Besides,  there 
are  now  such  microscopes  commonly  made,  that  the 
things  we  see  with  them  appear  a  hundred  thousand 
times  bigger  than  they  would  do  if  we  looked  upon 
them  with  our  bare  eyes.  Nor  is  there  any  doubt  but 
that  by  augmenting  the  power  of  these  microscopes 
(for  it  may  be  augmented  as  long  as  neither  matter 
nor  the  hands  of  workmen  are  wanting)  every  one  of 
those  hundred  thousandth  parts  might  yet  appear  a 
hundred  thousand  times  greater  than  they  did  before. 
Neither  is  the  smallness  of  some  bodies  to  be  more  ad- 
mired than  the  vast  greatness  of  others.  For  it  belongs 
to  the  same  Infinite  Power,  as  well  to  augment  infinitely 
as  infinitely  to  diminish.  To  make  the  great  orb, 
namely,  that  whose  radius  reacheth  from  the  earth  to 
the  sun,  but  as  a  point  in  respect  of  the  distance  be- 
tween the  sun  and  the  fixed  stars ;  and,  on  the  contrary, 
to  make  a  body  so  little,  as  to  be  in  the  same  proportion 
less  than  any  other  visible  body,  proceeds  equally  from 
one  and  the  same  Author  of  Nature.  But  this  of  the 
immense  distance  of  the  fixed  stars,  which  for  a  long 
time  was  accounted  an  incredible  thing,  is  now  believed 
by  almost  all  the  learned.  Why  then  should  not  that 
other,  of  the  smallness  of  some  bodies,  become  credible 
at  some  time  or  other?  For  the  Majesty  of  God  ap- 
pears no  less  in  small  things  than  in  great;  and  as  it 


OF  LIGHT,  HEAT,  AND  OF  COLOURS.         137 

exceedeth  human  sense  in  the  immense  greatness  of  the 
universe,  so  also  it  doth  in  the  smallness  of  the  parts 
thereof.  Nor  are  the  first  elements  of  compositions, 
nor  the  first  beginnings  of  actions,  nor  the  first  mo- 
ments of  times  more  credible,  than  that  which  is  now 
believed  of  the  vast  distance  of  the  fixed  stars. 

Some  things  are  acknowledged  by  mortal  men  to 
be  very  great,  though  finite,  as  seeing  them  to  be  such. 
They  acknowledge  also  that  some  things,  which  they 
do  not  see,  may  be  of  infinite  magnitude.  But  they 
are  not  presently  nor  without  great  study  persuaded, 
that  there  is  any  mean  between  infinite  and  the  great- 
est of  those  things  which  either  they  see  or  imagine. 
Nevertheless,  when  after  meditation  and  contempla- 
tion many  things  which  we  wondered  at  before  are 
now  grown  more  familiar  to  us,  we  then  believe  them, 
and  transfer  our  admiration  from  the  creatures  to  the 
Creator.  But  how  little  soever  some  bodies  may  be, 
yet  I  will  not  suppose  their  quantity  to  be  less  than  is 
requisite  for  the  solving  of  the  phenomena.  And  in 
like  manner  I  shall  suppose  their  motion,  namely,  their 
velocity  and  slowness,  and  the  variety  of  their  figures, 
to  be  only  such  as  the  explication  of  their  natural 
causes  requires.  And  lastly,  I  suppose,  that  the  parts 
of  the  pure  aether,  as  if  it  were  the  first  matter,  have 
no  motion  at  all  but  what  they  receive  from  bodies 
which  float  in  them,  and  are  not  themselves  fluid. 

2.  Having  laid  these  grounds,  let  us  come  to  speak 
of  causes ;  and  in  the  first  place  let  us  inquire  what 
may  be  the  cause  of  the  light  of  the  sun.  Seeing, 
therefore,  the  body  of  the  sun  doth  by  its  simple  circu- 
lar motion  thrust  away  the  ambient  ethereal  substance 
sometimes  one  way  sometimes  another,  so  that  those 
parts,  which  are  next  the  sun,  being  moved  by  it,  do 


138  CONCERNING  BODY. 

propagate  that  motion  to  the  next  remote  parts,  and 
these  to  the  next,  and  so  on  continually ;  it  must  needs 
be  that,  notwithstanding  any  distance,  the  foremost 
part  of  the  eye  will  at  last  be  pressed ;  and  by  the  pres- 
sure of  that  part,  the  motion  will  be  propagated  to  the 
innermost  part  of  the  organ  of  sight,  namely,  to  the 
heart;  and  from  the  reaction  of  the  heart,  there  will 
proceed  an  endeavour  back  by  the  same  way,  ending 
in  the  endeavour  outwards  of  the  coat  of  the  eye, 
called  the  retina.  But  this  endeavour  outwards,  as 
has  been  defined  in  chapter  xxv,  is  the  thing  which  is 
called  light,  or  the  phantasm  of  a  lucid  body.  For  it 
is  by  reason  of  this  phantasm  that  an  object  is  called 
lucid.  Wherefore  we  have  a  possible  cause  of  the 
light  of  the  sun ;  which  I  undertook  to  find. 

3.  The  generation  of  the  light  of  the  sun  is  accom- 
panied with  the  generation  of  heat.  Now  every  man 
knows  what  heat  is  in  himself,  by  feeling  it  when  he 
grows  hot;  but  what  it  is  in  other  things,  he  knows 
only  by  ratiocination.  For  it  is  one  thing  to  grow 
hot,  and  another  thing  to  heat  or  make  hot.  And 
therefore  though  we  perceive  that  the  fire  or  the  sun 
heateth,  yet  we  do  not  perceive  that  it  is  itself  hot. 
That  other  living  creatures,  whilst  they  make  other 
things  hot,  are  hot  themselves,  we  infer  by  reasoning 
from  the  like  sense  in  ourselves.  But  this  is  not  a 
necessary  inference.  For  though  it  may  truly  be 
said  of  living  creatures,  that  they  heat,  therefore  they 
are  themselves  hot;  yet  it  cannot  from  hence  be  truly 
inferred  that  fire  heateth,  therefore  it  is  itself  hot;  no 
more  than  this,  fire  canseth  pain,  therefore  it  is  itself 
in  pain.  Wherefore,  that  is  only  and  properly  called 
hot,  which  when  we  feel  we  are  necessarily  hot. 

Now  when  we  grow  hot,  we  find  that  our  spirits 


OF  LIGHT,  HEAT,  AND  OF  COLOURS.  139 

and  blood,  and  whatsoever  is  fluid  within  us,  is  called 
out  from  the  internal  to  the  external  parts  of  our  bod- 
ies, more  or  less,  according  to  the  degree  of  the  heat ; 
and  that  our  skin  swelleth.  He,  therefore,  that  can 
give  a  possible  cause  of  this  evocation  and  swelling, 
and  such  as  agrees  with  the  rest  of  the  phenomena  of 
heat,  may  be  thought  to  have  given  the  cause  of  the 
heat  of  the  sun. 

It  hath  been  shown,  in  the  5th  article  of  chapter 
xxi,  that  the  fluid  medium,  which  we  call  the  air,  is  so 
moved  by  the  simple  circular  motion  of  the  sun,  as 
that  all  its  parts,  even  the  least,  do  perpetually  change 
places  with  one  another ;  which  change  of  places  is 
that  which  there  I  called  fermentation.  From  this 
fermentation  of  the  air,  I  have,  in  the  8th  article  of  the 
last  chapter,  demonstrated  that  the  water  may  be 
drawn  up  into  the  clouds. 

And  I  shall  now  show  that  the  fluid  parts  may,  in 
like  manner,  by  the  same  fermentation,  be  drawn  out 
from  the  internal  to  the  external  parts  of  our  bodies. 
For  seeing  that  wheresoever  the  fluid  medium  is  con- 
tiguous to  the  body  of  any  living  creature,  there  the 
parts  of  that  medium  are,  by  perpetual  change  of 
place,  separated  from  one  another;  the  contiguous 
parts  of  the  living  creature  must,  of  necessity,  en- 
deavour to  enter  into  the  spaces  of  the  separated  parts. 
For  otherwise  those  parts,  supposing  there  is  no  vacu- 
um, would  have  no  place  to  go  into.  And  therefore 
that,  which  is  most  fluid  and  separable  in  the  parts  of 
the  living  creature  which  are  contiguous  to  the  me- 
dium, will  go  first  out ;  and  into  the  place  thereof  will 
succeed  such  other  parts  as  can  most  easily  transpire 
through  the  pores  of  the  skin.  And  from  hence  it  is 
necessary  that  the  rest  of  the  parts,  which  are  not  sep- 


i4o  CONCERNING  BODY. 

arated,  must  altogether  be  moved  outwards,  for  the 
keeping  of  all  places  full.  But  this  motion  outwards 
of  all  parts  together  must,  of  necessity,  press  those 
parts  of  the  ambient  air  which  are  ready  to  leave  their 
places,  and  therefore  all  the  parts  of  the  body,  en- 
deavouring at  once  that  way,  make  the  body  swell. 
Wherefore  a  possible  cause  is  given  of  heat  from  the 
sun ;  which  was  to  be  done. 


CHAPTER  XXVIII. 

OF  COLD,  WIND,  HARD,  ICE,  RESTITUTION  OF  BODIES 
BENT,  DIAPH0N0US,  LIGHTNING  AND  THUNDER  J  AND 
OF  THE  HEADS  OF  RIVERS. 

I.  Why  breath  from  the  same  mouth  sometimes  heats  and 
sometimes  cools. — 2.  Wind,  and  the  inconstancy  of  winds, 
whence. — 3.  Why  there  is  a  constant,  though  not  a  great 
wind,  from  east  to  west,  near  the  equator. — 4.  What  is  the 
effect  of  air  pent  in  between  the  clouds. — 5.  No  change  from 
soft  to  hard,  but  by  motion. — 6.  What  is  the  cause  of  cold 
near  the  poles. — 7.  The  cause  of  ice ;  and  why  the  cold  is 
more  remiss  in  rainy  than  in  clear  weather.  Why  water 
doth  not  freeze  in  deep  wells  as  it  doth  near  the  superficies 
of  the  earth.  Why  ice  is  not  so  heavy  as  water;  and  why 
wine  is  not  so  easily  frozen  as  water. — 8.  Another  cause  of 
hardness  from  the  fuller  contact  of  atoms ;  also,  how  hard 
things  are  broken. — 9.  A  third  cause  of  hardness  from  heat. 
10.  A  fourth  cause  of  hardness  from  the  motion  of  atoms 
enclosed  in  a  narrow  space. — 11.  How  hard  things  are  soft- 
ened.— 12.  Whence  proceed  the  spontaneous  restitution  of 
things  bent. — 13.  Diaphanous  and  opacous,  what  they  are, 
and  whence. — 14.  The  cause  of  lightning  and  thunder — 15. 
Whence  it  proceeds  that  clouds  can  fall  again  after  they  are 
once  elevated  and  frozen. — 16.  How  it  could  be  that  the 
moon  was  eclipsed,  when  she  was  not  diametrically  opposite 


OF  SOUND,  ODOUR,  SAVOUR,  AND  TOUCH.   141 

to  the  sun. — 17.  By  what  means  many  sums  may  appear  at 
once. — 18.  Of  the  heads  of  rivers. 

CHAPTER  XXIX. 

OF    SOUND,    ODOUR,    SAVOUR,    AND    TOUCH. 

I.  The  definition  of  sound,  and  the  distinctions  of  sounds. 
2.  The  cause  of  the  degrees  of  sounds. — 3.  The  difference 
between  sounds  acute  and  grave. — 4.  The  difference  between 
clear  and  hoarse  sounds,  whence. — 5.  The  sound  of  thunder 
and  of  a  gun,  whence  it  proceeds. — 6.  Whence  it  is  that 
pipes,  by  blowing  into  them,  have  a  clear  sound. — 7.  Of  re- 
flected sound. — 8.  From  whence  it  is  that  sound  is  uniform 
and  lasting. — 9.  How  sound  may  be  helped  and  hindered  by 
the  wind. — 10.  Not  only  air,  but  other  bodies  how  hard  so- 
ever they  be,  convey  sound. — 11.  The  causes  of  grave  and 
acute  sounds,  and  of  concent. — 12.  Phenomena  for  smelling. 
— 13.  The  first  organ  and  the  generation  of  smelling. — 14. 
How  it  is  helped  by  heat  and  by  wind. — 15.  Why  such  bodies 
are  least  smelt,  which  have  least  intermixture  of  air  in  them. 
— 16.  Why  odorous  things  become  more  odorous  by  being 
bruised. — 17.  The  first  organ  of  tasting;  and  why  some 
savours  cause  nauseousness. — 18.  The  first  organ  of  feeling; 
and  how  we  come  to  the  knowledge  of  such  objects  as  are 
common  to  the  touch  and  other  senses. 

i.  Sound  is  sense  generated  by  the  action  of  the 
medium,  when  its  motion  reacheth  the  ear  and  the  rest 
of  the  organs  of  sense.  Now,  the  motion  of  the  me- 
dium is  not  the  sound  itself,  but  the  cause  of  it.  For 
the  phantasm  which  is  made  in  us,  that  is  to  say,  the 
reaction  of  the  organ,  is  properly  that  which  we  call 
sound. 

The  principal  distinctions  of  sounds  are  these;  first, 
that  one  sound  is  stronger,  another  weaker.  Second- 
ly, that  one  is  more  grave,  another  more  acute. 
Thirdly,  that  one  is  clear,  another  hoarse.     Fourthly, 


142  CONCERNING  BODY. 

that  one  is  primary,  another  derivative.  Fifthly,  that 
one  is  uniform,  another  not.  Sixthly,  that  one  is  more 
durable,  another  less  durable.  Of  all  which  distinc- 
tions the  members  may  be  sub-distinguished  into  parts 
distinguishable  almost  infinitely.  For  the  variety  of 
sounds  seems  to  be  not  much  less  than  that  of  colours. 

As  vision,  so  hearing  is  generated  by  the  motion  of 
the  medium,  but  not  in  the  same  manner.  For  sight  is 
from  pressure,  that  is,  from  an  endeavour;  in  which 
there  is  no  perceptible  progression  of  any  of  the  parts 
of  the  medium;  but  one  part  urging  or  thrusting  on 
another  propagateth  that  action  successively  to  any 
distance  whatsoever;  whereas  the  motion  of  the  me- 
dium, by  which  sound  is  made,  is  a  stroke.  For  when 
we  hear,  the  drum  of  the  ear,  which  is  the  first  organ 
of  hearing,  is  stricken ;  and  the  drum  being  stricken, 
the  pia  mater  is  also  shaken,  and  with  it  the  arteries 
which  are  inserted  into  it;  by  which  the  action  being 
propagated  to  the  heart  itself,  by  the  reaction  of  the 
heart  a  phantasm  is  made  which  we  call  sound;  and 
because  the  reaction  tendeth  outwards,  we  think  it  is 
without. 

2.  And  seeing  the  effects  produced  by  motion  are 
greater  or  less,  not  only  when  the  velocity  is  greater 
or  less,  but  also  when  the  body  hath  greater  or  less 
magnitude  though  the  velocity  be  the  same;  a  sound 
may  be  greater  or  less  both  these  ways.  And  because 
neither  the  greatest  nor  the  least  magnitude  or  ve- 
locity can  be  given,  it  may  happen  that  either  the  mo- 
tion may  be  of  so  small  velocity,  or  the  body  itself  of 
so  small  magnitude,  as  to  produce  no  sound  at  all ;  or 
either  of  them  may  be  so  great,  as  to  take  away  the 
faculty  of  sense  by  hurting  the  organ. 

From  hence  may  be  deduced  possible  causes  of  the 


OF  SOUND,  ODOUR,  SAVOUR,  AND  TOUCH.      143 

strength  and  weakness  of  sounds  in  the  following 
phenomena. 

The  first  whereof  is  this,  that  if  a  man  speak 
through  a  trunk  which  hath  one  end  applied  to  the 
mouth  of  the  speaker,  and  the  other  to  the  ear  of  the 
hearer,  the  sound  will  come  stronger  than  it  would 
do  through  the  open  air.  And  the  cause,  not  only  the 
possible,  but  the  certain  and  manifest  cause  is  this, 
that  the  air  which  is  moved  by  the  first  breath  and 
carried  forwards  in  the  trunk,  is  not  diffused  as  it 
would  be  in  the  open  air,  and  is  consequently  brought 
to  the  ear  almost  with  the  same  velocity  with  which 
it  was  first  breathed  out.  Whereas,  in  the  open  air, 
the  first  motion  diffuseth  itself  every  way  into  circles, 
such  as  are  made  by  the  throwing  of  a  stone  into  a 
standing  water,  where  the  velocity  grows  less  and  less 
as  the  undulation  proceeds  further  and  further  from 
the  beginning  of  its  motion. 

The  second  is  this,  that  if  the  trunk  be  short,  and 
the  end  which  is  applied  to  the  mouth  be  wider  than 
that  which  is  applied  to  the  ear,  thus  also  the  sound 
will  be  stronger  than  if  it  were  made  in  the  open  air. 
And  the  cause  is  the  same,  namely,  that  by  how  much 
the  wider  end  of  the  trunk  is  less  distant  from  the 
beginning  of  the  sound,  by  so  much  the  less  is  the 
diffusion. 

The  third,  that  it  is  easier  for  one,  that  is  within  a 
chamber,  to  hear  what  is  spoken  without,  than  for 
him,  that  stands  without,  to  hear  what  is  spoken  with- 
in. For  the  windows  and  other  inlets  of  the  moved 
air  are  as  the  wide  end  of  the  trunk.  And  for  this 
reason  some  creatures  seem  to  hear  the  better,  because 
nature  has  bestowed  upon  them  wide  and  capacious 
ears. 


144  CONCERNING  BODY. 

The  fourth  is  this,  that  though  he,  which  standeth 
upon  the  sea-shore,  cannot  hear  the  collision  of  the 
two  nearest  waves,  yet  nevertheless  he  hears  the  roar- 
ing of  the  whole  sea.  And  the  cause  seems  to  be  this, 
that  though  the  several  collisions  move  the  organ,  yet 
they  are  not  severally  great  enough  to  cause  sense; 
whereas  nothing  hinders  but  that  all  of  them  together 
may  make  sound. 

3.  That  bodies  when  they  are  stricken  do  yield 
some  a  more  grave,  others  a  more  acute  sound,  the 
cause  may  consist  in  the  difference  of  the  times  in 
which  the  parts  stricken  and  forced  out  of  their  places 
return  to  the  same  places  again.  For  in  some  bodies, 
the  restitution  of  the  moved  parts  is  quick,  in  others 
slow.  And  this  also  may  be  the  cause,  why  the  parts 
of  the  organ,  which  are  moved  by  the  medium,  return 
to  their  rest  again,  sometimes  sooner,  sometimes  later. 
Now,  by  how  much  the  vibrations  or  the  reciprocal 
motions  of  the  parts  are  more  frequent,  by  so  much 
doth  the  whole  sound  made  at  the  same  time  by  one 
stroke  consist  of  more,  and  consequently  of  smaller 
parts.  For  what  is  acute  in  sound,  the  same  is  subtle 
in  matter ;  and  both  of  them,  namely  acute  sound  and 
subtle  matter,  consist  of  very  small  parts,  that  of  time, 
and  this  of  the  matter  itself. 

The  third  distinction  of  sounds  cannot  be  conceived 
clearly  enough  by  the  names  I  have  used  of  clear  and 
hoarse,  nor  by  any  other  that  I  know;  and  therefore 
it  is  needful  to  explain  them  by  examples.  When  I 
say  hoarse,  I  understand  whispering  and  hissing,  and 
whatsoever  is  like  to  these,  by  what  appellation  soever 
it  be  expressed.  And  sounds  of  this  kind  seem  to  be 
made  by  the  force  of  some  strong  wind,  raking  rather 
than  striking  such  hard  bodies  as  it  falls  upon.     On 


OF  SOUND,  ODOUR,  SAVOUR,  AND  TOUCH.      145 

the  contrary,  when  I  use  the  word  clear,  I  do  not  un- 
derstand such  a  sound  as  may  be  easily  and  distinctly 
heard ;  for  so  whispers  would  be  clear ;  but  such  as  is 
made  by  somewhat  that  is  broken,  and  such  as  is 
clamour,  tinkling,  the  sound  of  a  trumpet,  &c.,  and  to 
express  it  significantly  in  one  word,  noise.  And  see- 
ing no  sound  is  made  but  by  the  concourse  of  two 
bodies  at  the  least,  by  which  concourse  it  is  necessary 
that  there  be  as  well  reaction  as  action,  that  is  to  say, 
one  motion  opposite  to  another ;  it  follows  that  accord- 
ing as  the  proportion  between  those  two  opposite  mo- 
tions is  diversified,  so  the  sounds  which  are  made 
will  be  different  from  one  another.  And  whensoever 
the  proportion  between  them  is  so  great,  as  that  the 
motion  of  one  of  the  bodies  be  insensible  if  compared 
with  the  motion  of  the  other,  then  the  sound  will  not 
be  of  the  same  kind;  as  when  the  wind  falls  very  ob- 
liquely upon  a  hard  body,  or  when  a  hard  body  is  car- 
ried swiftly  through  the  air;  for  then  there  is  made 
that  sound  which  I  call  a  hoarse  sound,  in  Greek 
(Tvpty/xos.  Therefore  the  breath  blown  with  violence 
from  the  mouth  makes  a  hissing,  because  in  going  out 
it  rakes  the  superficies  of  the  lips,  whose  reaction 
against  the  force  of  the  breath  is  not  sensible.  And 
this  is  the  cause  why  the  winds  have  that  hoarse  sound. 
Also  if  two  bodies,  how  hard  soever,  be  rubbed  to- 
gether with  no  great  pressure,  they  make  a  hoarse 
sound.  And  this  hoarse  sound,  when  it  is  made,  as 
I  have  said,  by  the  air  raking  the  superficies  of  a  hard 
body,  seemeth  to  be  nothing  but  the  dividing  of  the 
air  into  innumerable  and  very  small  files.  For  the 
asperity  of  the  superficies  doth,  by  the  eminences  of 
its  innumerable  parts,  divide  or  cut  in  pieces  the  air 
that  slides  upon  it. 


146  CONCERNING  BODY. 

4.  Noise,  or  that  which  I  call  clear  sound,  is  made 
two  ways;  one,  by  two  hoarse  sounds  made  by  oppo- 
site motions;  the  other,  by  collision,  or  by  the  sudden 
pulling  asunder  of  two  bodies,  whereby  their  small 
particles  are  put  into  commotion,  or  being  already  in 
commotion  suddenly  restore  themselves  again;  which 
motion,  making  impression  upon  the  medium,  is  prop- 
agated to  the  organ  of  hearing.  And  seeing  there  is 
in  this  collision  or  divulsion  an  endeavour  in  the  par- 
ticles of  one  body,  opposite  to  the  endeavour  of  the 
particles  of  the  other  body,  there  will  also  be  made  in 
the  organ  of  hearing  a  like  opposition  of  endeavours, 
that  is  to  say,  of  motions ;  and  consequently  the  sound 
arising  from  thence  will  be  made  by  two  opposite 
motions,  that  is  to  say,  by  two  opposite  hoarse  sounds 
in  one  and  the  same  part  of  the  organ.  For,  as  I 
have  already  said,  a  hoarse  sound  supposeth  the  sensi- 
ble motion  of  but  one  of  the  bodies.  And  this  oppo- 
sition of  motions  in  the  organ  is  the  cause  why  two 
bodies  make  a  noise,  when  they  are  either  suddenly 
stricken  against  one  another,  or  suddenly  broken 
asunder. 

12.  For  the  rinding  out  the  cause  of  smells,  I  shall 
make  use  of  the  evidence  of  these  following  phenom- 
ena. First,  that  smelling  is  hindered  by  cold,  and 
helped  by  heat.  Secondly,  that  when  the  wind  blow- 
eth  from  the  object,  the  smell  is  the  stronger;  and, 
contrarily,  when  it  bloweth  from  the  sentient  towards 
the  object,  the  weaker;  both  which  phenomena  are, 
by  experience,  manifestly  found  to  be  true  in  dogs, 
which  follow  the  track  of  beasts  by  the  scent.  Third- 
ly, that  such  bodies,  as  are  less  pervious  to  the  fluid 
medium,  yield  less  smell  than  such  as  are  more  per- 


OF  SOUND,  ODOUR,  SAVOUR,  AND  TOUCH.      147 

vious ;  as  may  be  seen  in  stones  and  metals,  which, 
compared  with  plants  and  living  creatures,  and  their 
parts,  fruits  and  excretions,  have  very  little  or  no 
smell  at  all.  Fourthly,  that  such  bodies,  as  are  of 
their  own  nature  odorous,  become  yet  more  odorous 
when  they  are  bruised.  Fifthly,  that  when  the  breath 
is  stopped,  at  least  in  men,  nothing  can  be  smelt. 
Sixthly,  that  the  sense  of  smelling  is  also  taken  away 
by  the  stopping  of  the  nostrils,  though  the  mouth  be 
left  open. 

13.  By  the  fifth  and  sixth  phenomenon  it  is  mani- 
fest, that  the  first  and  immediate  organ  of  smelling 
is  the  innermost  cuticle  of  the  nostrils,  and  that  part 
of  it,  which  is  below  the  passage  common  to  the  nos- 
trils and  the  palate.  For  when  we  draw  breath  by 
the  nostrils  we  draw  it  into  the  lungs.  That  breath, 
therefore,  which  conveys  smells  is  in  the  way  which 
passeth  to  the  lungs,  that  is  to  say,  in  that  part  of  the 
nostrils  which  is  below  the  passage  through  which 
the  breath  goeth.  For,  nothing  is  smelt,  neither  be- 
yond the  passage  of  the  breath  within,  nor  at  all  with- 
out the  nostrils. 

And  seeing  that  from  different  smells  there  must 
necessarily  proceed  some  mutation  in  the  organ,  and 
all  mutation  is  motion;  it  is  therefore  also  necessary 
that,  in  smelling,  the  parts  of  the  organ,  that  is  to  say  of 
that  internal  cuticle  and  the  nerves  that  are  inserted  in- 
to it,  must  be  diversely  moved  by  different  smells.  And 
seeing  also,  that  it  hath  been  demonstrated,  that  noth- 
ing can  be  moved  but  by  a  body  that  is  already  moved 
and  contiguous ;  and  that  there  is  no  other  body  con- 
tiguous to  the  internal  membrane  of  the  nostrils  but 
breath,  that  is  to  say  attracted  air,  and  such  little  solid 
invisible  bodies,  if  there  be  any  such,  as  are  intermin- 


i48  CONCERNING  BODY. 

gled  with  the  air ;  it  follows  necessarily,  that  the  cause 
of  smelling  is  either  the  motion  of  that  pure  air  or 
ethereal  substance,  or  the  motion  of  those  small  bod- 
ies. But  this  motion  is  an  effect  proceeding  from  the 
object  of  smell,  and  therefore,  either  the  whole  object 
itself  or  its  several  parts  must  necessarily  be  moved. 
Now,  we  know  that  odorous  bodies  make  odour, 
though  their  whole  bulk  be  not  moved.  Wherefore 
the  cause  of  odour  is  the  motion  of  the  invisible  parts 
of  the  odorous  body.  And  these  invisible  parts  do 
either  go  out  of  the  object,  or  else,  retaining  their 
former  situation  with  the  rest  of  the  parts,  are  moved 
together  with  them,  that  is  to  say,  they  have  simple 
and  invisible  motion.  They  that  say,  there  goes 
something  out  of  the  odorous  body,  call  it  an  efflu- 
vium ;  which  effluvium  is  either  of  the  ethereal  sub- 
stance, or  of  the  small  bodies  that  are  intermingled 
with  it.  But,  that  all  variety  of  odours  should  pro- 
ceed from  the  effluvia  of  those  small  bodies  that  are 
intermingled  with  the  ethereal  substance,  is  altogether 
incredible,  for  these  considerations ;  first,  that  certain 
unguents,  though  very  little  in  quantity,  do  neverthe- 
less send  forth  very  strong  odours,  not  only  to  a  great 
distance  of  place,  but  also  for  a  great  continuance  of 
time,  and  are  to  be  smelt  in  every  point  both  of  that 
place  and  time;  so  that  the  parts  issued  out  are  suffi- 
cient to  fill  ten  thousand  times  more  space,  than  the 
whole  odorous  body  is  able  to  fill ;  which  is  impossi- 
ble. Secondly,  that  whether  that  issuing  out  be  with 
strait  or  with  crooked  motion,  if  the  same  quantity 
should  flow  from  any  other  odorous  body  with  the 
same  motion,  it  would  follow  that  all  odorous  bodies 
would  yield  the  same  smell.  Thirdly,  that  seeing 
those  effluvia  have  great   velocity   of  motion    (as   is 


OF  SOUND,  ODOUR,  SAVOUR,  AND  TOUCH.      149 

manifest  from  this,  that  noisome  odours  proceeding 
from  caverns  are  presently  smelt  at  a  great  distance) 
it  would  follow,  that,  by  reason  there  is  nothing  to 
hinder  the  passage  of  those  effluvia  to  the  organ,  such 
motion  alone  were  sufficient  to  cause  smelling;  which 
is  not  so;  for  we  cannot  smell  at  all,  unless  we  draw 
in  our  breath  through  our  nostrils.  Smelling,  there- 
fore, is  not  caused  by  the  effluvium  of  atoms ;  nor,  for 
the  same  reason,  is  it  caused  by  the  effluvium  of 
ethereal  substance;  for  so  also  we  should  smell  with- 
out the  drawing  in  of  our  breath.  Besides,  the  ethe- 
real substance  being  the  same  in  all  odorous  bodies, 
they  would  always  affect  the  organ  in  the  same  man- 
ner ;  and,  consequently,  the  odours  of  all  things  would 
be  alike. 

It  remains,  therefore,  that  the  cause  of  smelling 
must  consist  in  the  simple  motion  of  the  parts  of 
odorous  bodies  without  any  efflux  or  diminution  of 
their  whole  substance.  And  by  this  motion  there  is 
propagated  to  the  organ,  by  the  intermediate  air,  the 
like  motion,  but  not  strong  enough  to  excite  sense  of 
itself  without  the  attraction  of  air  by  respiration. 
And  this  is  a  possible  cause  of  smelling. 

14.  The  cause  why  smelling  is  hindered  by  cold 
and  helped  by  heat  may  be  this;  that  heat,  as  hath 
been  shown  in  chapter  xxi,  generateth  simple  motion ; 
and  therefore  also,  wheresoever  it  is  already,  there  it 
will  increase  it;  and  the  cause  of  smelling  being  in- 
creased, the  smell  itself  will  also  be  increased.  As 
for  the  cause  why  the  wind  blowing  from  the  object 
makes  the  smell  the  stronger,  it  is  all  one  with  that 
for  which  the  attraction  of  air  in  respiration  doth  the 
same.  For,  he  that  draws  in  the  air  next  to  him, 
draws  with  it  by  succession  that  air  in  which  is  the 


I5Q  CONCERNING  BODY. 

object.  Now,  this  motion  of  the  air  is  wind,  and, 
when  another  wind  bloweth  from  the  object,  will  be 
increased  by  it. 

15.  That  bodies  which  contain  the  least  quantity 
of  air,  as  stones  and  metals,  yield  less  smell  than 
plants  and  living  creatures;  the  cause  may  be,  that 
the  motion,  which  causeth  smelling,  is  a  motion  of  the 
fluid  parts  only ;  which  parts,  if  they  have  any  motion 
from  the  hard  parts  in  which  they  are  contained,  they 
communicate  the  same  to  the  open  air,  by  which  it  is 
propagated  to  the  organ.  Where,  therefore,  there 
are  no  fluid  parts  as  in  metals,  or  where  the  fluid  parts 
receive  no  motion  from  the  hard  parts,  as  in  stones, 
which  are  made  hard  by  accretion,  there  can  be  no 
smell.  And  therefore  also  the  water,  whose  parts 
have  little  or  no  motion,  yieldeth  no  smell.  But,  if 
the  same  water,  by  seeds  and  the  heat  of  the  sun,  be 
together  with  particles  of  earth  raised  into  a  plant, 
and  be  afterwards  pressed  out  again,  it  will  be  odorous, 
as  wine  from  the  vine.  And  as  water  passing 
through  plants  is  by  the  motion  of  the  parts  of  those 
plants  made  an  odorous  liquor,  so  also  of  air,  passing 
through  the  same  plants  whilst  they  are  growing,  are 
made  odorous  airs.  And  thus  also  it  is  with  the 
juices  and  spirits,  which  are  bred  in  living  creatures. 

16.  That  odorous  bodies  may  be  made  more  odor- 
ous by  contrition  proceeds  from  this,  that  being  brok- 
en into  many  parts,  which  are  all  odorous,  the  air, 
which  by  respiration  is  drawn  from  the  object  towards 
the  organ,  doth  in  its  passage  touch  upon  all  those 
parts,  and  receive  their  motion.  Now,  the  air  touch- 
eth  the  superficies  only ;  and  a  body  having  less  super- 
ficies whilst  it  is  whole,  than  all  its  parts  together 
have  after  it  is  reduced  to  powder,  it  follows  that  the 


OF  SOUND,  ODOUR,  SAVOUR,  AND  TOUCH.       151 

same  odorous  body  yieldeth  less  smell  whilst  it  is 
whole,  than  it  will  do  after  it  is  broken  into  smaller 
parts.     And  thus  much  of  smells. 

17.  The  taste  follows;  whose  generation  hath  this 
difference  from  that  of  the  sight,  hearing,  and  smell- 
ing, that  by  these  we  have  sense  of  remote  objects ; 
whereas,  we  taste  nothing  but  what  is  contiguous,  and 
doth  immediately  touch  either  the  tongue  or  palate,  or 
both.  From  whence  it  is  evident,  that  the  cuticles  of 
the  tongue  and  palate,  and  the  nerves  inserted  into 
them  are  the  first  organ  of  taste;  and  (because  from 
the  concussion  of  the  parts  of  these,  there  followeth 
necessarily  a  concussion  of  the  pia  mater)  that  the 
action  communicated  to  these  is  propagated  to  the 
brain,  and  from  thence  to  the  farthest  organ,  namely, 
the  heart,  in  whose  reaction  consisteth  the  nature  of 
sense. 

Now,  that  savours,  as  well  as  odours,  do  not  only 
move  the  brain  but  the  stomach  also,  as  is  manifest 
by  the  loathings  that  are  caused  by  them  both;  they, 
that  consider  the  organ  of  both  these  senses,  will  not 
wonder  at  all;  seeing  the  tongue,  the  palate  and  the 
nostrils,  have  one  and  the  same  continued  cuticle,  de- 
rived from  the  dura  mater. 

And  that  effluvia  have  nothing  to  do  in  the  sense  of 
tasting,  is  manifest  from  this,  that  there  is  no  taste 
where  the  organ  and  the  object  are  not  contiguous. 

By  what  variety  of  motions  the  different  kinds  of 
tastes,  which  are  innumerable,  may  be  distinguished, 
I  know  not.  I  might  with  others  derive  them  from 
the  divers  figures  of  those  atoms,  of  which  whatsoever 
may  be  tasted  consisteth ;  or  from  the  diverse  motions 
which  I  might,  by  way  of  supposition,  attribute  to 
those  atoms;  conjecturing,  not   without  some  likeli- 


152  CONCERNING  BODY. 

hood  of  truth,  that  such  things  as  taste  sweet  have 
their  particles  moved  with  slow  circular  motion,  and 
their  figures  spherical;  which  makes  them  smooth  and 
pleasing  to  the  organ ;  that  bitter  things  have  circular 
motion,  but  vehement,  and  their  figures  full  of  an- 
gles, by  which  they  trouble  the  organ ;  and  that  sour 
things  have  strait  and  reciprocal  motion,  and  their 
figures  long  and  small,  so  that  they  cut  and  wound 
the  organ.  And  in  like  manner  I  might  assign  for 
the  causes  of  other  tastes  such  several  motions  and 
figures  of  atoms,  as  might  in  probability  seem  to  be 
the  true  causes.  But  this  would  be  to  revolt  from 
philosophy  to  divination. 

1 8.  By  the  touch  we  feel  what  bodies  are  cold  or 
hot,  though  they  be  distant  from  us.  Others,  as  hard, 
soft,  rough,  and  smooth,  we  cannot  feel  unless  they 
be  contiguous.  The  organ  of  touch  is  every  one  of 
those  membranes,  which  being  continued  from  the 
pia  mater  are  so  diffused  throughout  the  whole  body, 
as  that  no  part  of  it  can  be  pressed,  but  the  pia  mater 
is  pressed  together  with  it.  Whatsoever  therefore 
presseth  it,  is  felt  as  hard  or  soft,  that  is  to  say,  as 
more  or  less  hard.  And  as  for  the  sense  of  rough,  it 
is  nothing  else  but  innumerable  perceptions  of  hard 
and  hard  succeeding  one  another  by  short  intervals 
both  of  time  and  place.  For  we  take  notice  of  rough 
and  smooth,  as  also  of  magnitude  and  figure,  not 
only  by  the  touch,  but  also  by  memory.  For  though 
some  things  are  touched  in  one  point,  yet  rough  and 
smooth,  like  quantity  and  figure,  are  not  perceived 
but  by  the  flux  of  a  point,  that  is  to  say,  we  have  no 
sense  of  them  without  time ;  and  we  can  have  no  sense 

of  time  without  memory. 

********* 


OF  GRAVITY.  153 

CHAPTER  XXX. 


OF     GRAVITY. 

r.  A  thick  body  doth  not  contain  more  matter,  unless  also 
more  place,  than  a  thin. — 2.  That  the  descent  of  heavy  bod- 
ies proceeds  not  from  their  own  appetite,  but  from  some 
power  of  the  earth. — 3.  The  difference  of  gravities  proceed- 
eth  from  the  difference  of  the  impetus  with  which  the  ele- 
ments, whereof  heavy  bodies  are  made,  do  fall  upon  the 
earth. — 4.  The  cause  of  the  descent  of  heavy  bodies. — 5.  In 
what  proportion  the  descent  of  heavy  bodies  is  accelerated. — 
6.  Why  those  that  dive  do  not,  when  they  are  under  water, 
feel  the  weight  of  the  water  above  them. — 7.  The  weight  of 
a  body  that  floateth,  is  equal  to  the  weight  of  so  much 
water  as  would  fill  the  space,  which  the  immersed  part  of  the 
body  takes  up  within  the  water. — 8.  If  a  body  be  lighter 
than  water,  then  how  big  soever  that  body  be,  it  may  float 
upon  any  quantity  of  water,  how  little  soever. — 9.  How 
water  may  be  lifted  up  and  forced  out  of  a  vessel  by  air. — 
10.  Why  a  bladder  is  heavier  when  blown  full  of  air,  than 
when  it  is  empty. — 11.  The  cause  of  the  ejection  upwards 
of  heavy  bodies  from  a  wind-gun. — 12.  The  cause  of  the 
ascent  of  water  in  a  weather-glass. — 13.  The  cause  of  mo- 
tion upwards  in  living  creatures. — 14.  That  there  is  in  nature 
a  kind  of  body  heavier  than  air,  which  nevertheless  is  not  by 
sense  distinguishable  from  it. — 15.  Of  the  cause  of  magnet- 
ical  virtue. 


15.  And  thus  much  concerning  the  nature  of  body 
in  general;  with  which  I  conclude  this  my  first  sec- 
tion of  the  Elements  of  Philosophy.  In  the  first,  sec- 
ond, and  third  parts,  where  the  principles  of  ratio- 
cination consist  in  our  own  understanding,  that  is  to 
say,  in  the  legitimate  use  of  such  words  as  we  our- 
selves constitute,  all  the  theorems,  if  I  be  not  de- 
ceived,  are   rightly   demonstrated.    The   fourth   part 


154  CONCERNING  BODY. 

depends  upon  hypotheses;  which  unless  we  know 
them  to  be  true,  it  is  impossible  for  us  to  demonstrate 
that  those  causes,  which  I  have  there  explicated,  are 
the  true  causes  of  the  things  whose  productions  I  have 
derived  from  them. 

Nevertheless,  seeing  I  have  assumed  no  hypothesis, 
which  is  not  both  possible  and  easy  to  be  compre- 
hended; and  seeing  also  that  I  have  reasoned  aright 
from  those  assumptions,  I  have  withal  sufficiently 
demonstrated  that  they  may  be  the  true  causes ;  which 
is  the  end  of  physical  contemplation.  If  any  other 
man  from  other  hypotheses  shall  demonstrate  the 
same  or  greater  things,  there  will  be  greater  praise 
and  thanks  due  to  him  than  I  demand  for  myself,  pro- 
vided his  hypotheses  be  such  as  are  conceivable.  For 
as  for  those  that  say  anything  may  be  moved  or  pro- 
duced by  itself,  by  species,  by  its  own  power,  by 
substantial  forms,  by  incorporeal  substances,  by  in- 
stinct, by  antiperistasis,  by  antipathy,  sympathy,  oc- 
cult quality,  and  other  empty  words  of  schoolmen, 
their  saying  so  is  to  no  purpose. 

And  now  I  proceed  to  the  phenomena  of  man's 
body;  where  I  shall  speak  of  the  optics,  and  of  the 
dispositions,  affections,  and  manners  of  men,  if  it  shall 
please  God  to  give  me  life,  and  show  their  causes. 


THE  DOCTRINE  OF  HOBBES  CONCERNING 
THE  UNREALITY  OF  CON- 
SCIOUSNESS. 


HUMAN  NATURE. 
CHAPTER  II. 


HUMAN  NATURE. 

CHAPTER  II. 

2.  Definition  of  sense.  4.  Four  propositions  concerning  the 
nature  of  conceptions.  5.  The  first  proved.  6.  The  second 
proved.  7,  8.  The  third  proved.  9.  The  fourth  proved. 
10.  The  main  deception  of  sense. 

i.  Having  declared  what  I  mean  by  the  word 
conception,  and  other  words  equivalent  thereunto,  I 
come  to  the  conceptions  themselves,  to  shew  their  dif- 
ferences, their  causes,  and  the  manner  of  the  produc- 
tion, so  far  as  is  necessary  for  this  place. 

2.  Originally  all  conceptions  proceed  from  the  ac- 
tion of  the  thing  itself,  whereof  it  is  the  conception: 
now  when  the  action  is  present,  the  conception  it  pro- 
duceth  is  also  called  sense;  and  the  thing  by  whose 
action  the  same  is  produced,  is  called  the  object  of 
the  sense.' 

3.  By  our  several  organs  we  have  several  concep- 
tions of  several  qualities  in  the  objects ;  for  by  sight 
we  have  a  conception  or  image  composed  of  colour 
and  tig ure,  which  is  all  the  notice  and  knowledge  the 
object  imparteth  to  us  of  its  nature  by  the  eye.  By 
hearing  we  have  a  conception  called  sound,  which  is 
all  the  knowledge  we  have  of  the  quality  of  the  object 
from  the  ear.  And  so  the  rest  of  the  senses  are  also 
conceptions  of  several  qualities,  or  natures  of  their 
objects. 

4.  Because  the  image  in  vision  consisting  of  colour 
and  shape  is  the  knowledge  we  have  of  the  qualities 
of  the  object  of  that  sense;  it  is  no  hard  matter  for 

i57 


158  HUMAN  NATURE. 

a  man  to  fall  into  this  opinion,  that  the  same  colour 
and  shape  are  the  very  qualities  themselves ;  and  for 
the  same  cause,  that  sound  and  noise  are  the  qualities 
of  the  bell,  or  of  the  air.  And  this  opinion  hath  been 
so  long  received,  that  the  contrary  must  needs  appear 
a  great  paradox;  and  yet  the  introduction  of  species 
visible  and  intelligible  (which  is  necessary  for  the 
maintenance  of  that  opinion)  passing  to  and  fro  from 
the  object,  is  worse  than  any  paradox,  as  being  a  plain 
impossibility.  I  shall  therefore  endeavour  to  make 
plain  these  points : 

That  the  subject  wherein  colour  and  image  are  in- 
herent, is  not  the  object  or  thing  seen. 

That  there  is  nothing  without  us  (really)  which  we 
call  an  image  or  colour. 

That  the  said  image  or  colour  is  but  an  apparition 
unto  us  of  the  motion,  agitation,  or  alteration,  which 
the  object  worketh  in  the  brain,  or  spirit,  or  some  in- 
ternal substance  of  the  head. 

That  as  in  vision,  so  also  in  conceptions  that  arise 
from  the  other  senses,  the  subject  of  their  inherence  is 
not  the  object,  but  the  sentient. 

5.  Every  man  hath  so  much  experience  as  to  have 
seen  the  sun  and  the  other  visible  objects  by  reflection 
in  the  water  and  glasses;  and  this  alone  is  sufficient  for 
this  conclusion,  that  colour  and  image  may  be  there 
where  the  thing  seen  is  not.  But  because  it  may  be 
said  that  notwithstanding  the  image  in  the  water  be 
not  in  the  object,  but  a  thing  merely  phantastical, 
yet  there  may  be  colour  really  in  the  thing  itself:  I 
will  urge  further  this  experience,  that  divers  times  men 
see  directly  the  same  object  double,  as  two  candles  for 
one,  which  may  happen  from  distemper,  or  otherwise 
without  distemper  if  a  man  will,  the  organs  being 


HUMAN  NATURE.  159 

either  in  their  right  temper,  or  equally  distempered; 
the  colours  and  figures  in  two  such  images  of  the 
same  thing  cannot  be  inherent  therein,  because  the 
thing  seen  cannot  be  in  two  places. 

One  of  these  images  therefore  is  not  inherent  in  the 
object:  but  seeing  the  organs  of  the  sight  are  then  in 
equal  temper  or  distemper,  the  one  of  them  is  no  more 
inherent  than  the  other ;  and  consequently  neither  of 
them  both  are  in  the  object;  which  is  the  first  proposi- 
tion, mentioned  in  the  precedent  number. 

6.  Secondly,  that  the  image  of  any  thing  by  re- 
flection in  a  glass  or  zvater  or  the  like,  is  not  any  thing 
in  or  behind  the  glass,  or  in  or  under  the  water,  every 
man  may  grant  to  himself;  which  is  the  second  propo- 
sition. 

7.  For  the  third,  we  are  to  consider,  first  that  upon 
every  great  agitation  or  concussion  of  the  brain  (as  it 
happeneth  from  a  stroke,  especially  if  the  stroke  be 
upon  the  eye)  whereby  the  optic  nerve  suffereth  any 
great  violence,  there  appeareth  before  the  eyes  a  cer- 
tain light,  which  light  is  nothing  without,  but  an  ap- 
parition only,  all  that  is  real  being  the  concussion  or 
motion  of  the  parts  of  that  nerve;  from  which  ex- 
perience we  may  conclude,  that  apparition  of  light  is 
really  nothing  but  motion  within.  If  therefore  from 
lucid  bodies  there  can  be  derived  motion,  so  as  to  affect 
the  optic  nerve  in  such  manner  as  is  proper  thereunto, 
there  will  follow  an  image  of  light  somewhere  in  that 
line  by  which  the  motion  was  last  derived  to  the  eye; 
that  is  to  say,  in  the  object,  if  we  look  directly  on  it, 
and  in  the  glass  or  water,  when  we  look  upon  it  in 
the  line  of  reflection,  which  in  effect  is  the  third  propo- 
sition ;  namely,  that  image  and  colour  is  but  an  appari- 
tion to  us  of  that  motion,  agitation,  or  alteration  which 


160  HUMAN  NATURE. 

the  object  worketh  in  the  brain  or  spirits,  or  some 
internal  substance  in  the  head. 

8.  But  that  from  all  lucid,  shining  and  illuminate 
bodies,  there  is  a  motion  produced  to  the  eye,  and, 
through  the  eye,  to  the  optic  nerve,  and  so  into  the 
brain,  by  which  that  apparition  of  light  or  colour  is 
affected,  is  not  hard  to  prove.  And  first,  it  is  evident 
that  the  fire,  the  only  lucid  body  here  upon  earth, 
worketh  by  motion  equally  every  way;  insomuch  as 
the  motion  thereof  stopped  or  inclosed,  it  is  presently 
extinguished,  and  no  more  fire.  And  further,  that  that 
motion,  whereby  the  fire  worketh,  is  dilation,  and  con- 
traction of  itself  alternately,  commonly  called  scintilla- 
tion or  glowing,  is  manifest  also  by  experience. 
From  such  motion  in  the  fire  must  needs  arise  a  rejec- 
tion or  casting  from  itself  of  that  part  of  the  medium 
which  is  contiguous  to  it,  whereby  that  part  also  re- 
jecteth  the  next,  and  so  successively  one  part  beateth 
back  another  to  the  very  eye;  and  in  the  same  manner 
the  exterior  part  of  the  eye  presseth  the  interior,  (the 
laws  of  refraction  still  observed).  Now  the  interior 
coat  of  the  eye  is  nothing  else  but  a  piece  of  the  optic 
nerve;  and  therefore  the  motion  is  still  continued 
thereby  into  the  brain,  and  by  resistance  or  reaction  of 
the  brain,  is  also  a  rebound  into  the  optic  nerve  again ; 
which  we  not  conceiving  as  motion  or  rebound  from 
within,  do  think  it  is  without,  and  call  it  light;  as  hath 
been  already  shewed  by  the  experience  of  a  stroke. 
We  have  no  reason  to  doubt,  that  the  fountain  of 
light,  the  sun,  worketh  by  any  other  ways  than  the  tire, 
at  least  in  this  matter.  And  thus  all  vision  hath  its 
original  from  such  motion  as  is  here  described:  for 
where  there  is  no  light,  there  is  no  sight ;  and  therefore 
colour  also  must  be  the  same  thing  with  light,  as  being 


HUMAN  NATURE.  161 

the  effect  of  the  lucid  bodies:  their  difference  being 
only  this,  that  when  the  light  cometh  directly  from  the 
fountain  to  the  eye,  or  indirectly  by  reflection  from 
clean  and  polite  bodies,  and  such  as  have  not  any  par- 
ticular motion  internal  to  alter  it,  we  call  it  light; 
but  when  it  cometh  to  the  eye  by  reflection  from 
uneven,  rough,  and  coarse  bodies,  or  such  as  are 
affected  with  internal  motion  of  their  own  that  may 
alter  it,  then  we  call  it  colour;  colour  and  light  differ- 
ing only  in  this,  that  the  one  is  'pure,  and  the  other 
perturbed  light.  By  that  which  hath  been  said,  not 
only  the  truth  of  the  third  proposition,  but  also  the 
whole  manner  of  producing  light  and  colour,  is  ap- 
parent. 

9.  As  colour  is  not  inherent  in  the  object,  but  an 
effect  thereof  upon  us,  caused  by  such  motion  in  the 
object,  as  hath  been  described:  so  neither  is  sound 
in  the  thing  we  hear,  but  in  ourselves.  One  manifest 
sign  thereof  is,  that  as  a  man  may  see,  so  also  he  may 
hear  double  or  treble,  by  multiplication  of  echoes, 
which  echoes  are  sounds  as  well  as  the  original;  and 
not  being  in  one  and  the  same  place,  cannot  be  inherent 
in  the  body  that  maketh  them.  Nothing  can  make  any 
thing  which  is  not  in  itself :  the  clapper  hath  no  sound 
in  it,  but  motion,  and  maketh  motion  in  the  internal 
parts  of  the  bell;  so  the  bell  hath  motion,  and  not 
sound,  that  imparteth  motion  to  the  air;  and  the  air 
hath  motion,  but  not  sound;  the  air  imparteth  motion 
by  the  ear  and  nerve  unto  the  brain;  and  the  brain  hath 
motion  but  not  sound;  from  the  brain,  it  reboundeth 
back  into  the  nerves  outward,  and  thence  it  becometh 
an  apparition  without,  which  we  call  sound.  And  to 
proceed  to  the  rest  of  the  senses,  it  is  apparent  enough, 
that  the  smell  and  taste  of  the  same  thing,  are  not  the 


162  HUMAN  NATURE. 

same  to  every  man;  and  therefore  are  not  in  the  thing 
smelt  or  tasted,  but  in  the  men.  So  likewise  the  heat 
we  feel  from  the  fire  is  manifestly  in  us,  and  is  quite 
different  from  the  heat  which  is  in  the  fire:  for  our 
heat  is  pleasure  or  Ipain,  according  as  it  is  great  or 
moderate;  but  in  the  coal  there  is  no  such  thing.  By 
this  the  fourth  and  last  proposition  is  proved,  viz. 
that  as  in  vision,  so  also  in  conceptions  that  arise  from 
other  senses,  the  subject  of  their  inherence  is  not  in 
the  object,  but  in  the  sentient. 

10.  And  from  hence  also  it  followeth,  that  whatso- 
ever accidents  or  qualities  our  senses  make  us  think 
there  be  in  the  world,  they  be  not  there,  but  are  seem- 
ing and  apparitions  only :  the  things  that  really  are  in 
the  world  without  us,  are  those  motions  by  which  these 
seemings  are  caused.  And  this  is  the  great  deception 
of  sense,  which  also  is  to  be  by  sense  corrected:  for  as 
sense  telleth  me,  when  I  see  directly,  that  the  colour 
seemeth  to  be  in  the  object;  so  also  sense  telleth  me, 
when  I  see  by  reflection,  that  colour  is  not  fa  the 
object. 


THE  DOCTRINE  OF  HOBBES  CONCERNING 

THE  NATURE  OF  SPIRIT  AND 

OF  GOD 


SELECTIONS  FROM  LEVIATHAN. 
CHAPTERS   XI,   XII,  XXXI,  XXXIV. 


LEVIATHAN 
PART  I. 

CHAPTER  XL 

OF  THE   DIFFERENCE   OF   MANNERS. 


Curiosity,  or  love  of  the  knowledge  of  causes,  draws 
a  man  from  the  consideration  of  the  effect,  to  seek 
the  cause;  and  again,  the  cause  of  that  cause;  till  of 
necessity  he  must  come  to  this  thought  at  last,  that  there 
is  some  cause,  whereof  there  is  no  former  cause,  but  is 
eternal;  which  is  it  men  call  God.  So  that  it  is  im- 
possible to  make  any  profound  inquiry  into  natural 
causes,  without  being  inclined  thereby  to  believe  there 
is  one  God  eternal ;  though  they  cannot  have  any  idea 
of  him  in  their  mind,  answerable  to  his  nature.  For  as 
a  man  that  is  born  blind,  hearing  men  talk  of  warming 
themselves  by  the  fire,  and  being  brought  to  warm 
himself  by  the  same,  may  easily  conceive,  and  assure 
himself,  there  is  somewhat  there,  which  men  call  fire, 
and  is  the  cause  of  the  heat  he  feels;  but  cannot 
imagine  what  it  is  like ;  nor  have  an  idea  of  it  in  his 
mind,  such  as  they  have  that  see  it:  so  also  by  the 
visible  things  in  this  world,  and  their  admirable  order, 
a  man  may  conceive  there  is  a  cause  of  them,  which 

165 


166  LEVIATHAN. 

men  call  God;  and  yet  not  have  an  idea,  or  image 
of  him  in  his  mind. 

And  they  that  make  little,  or  no  inquiry  into  the 
natural  causes  of  things,  yet  from  the  fear  that  pro- 
ceeds from  the  ignorance  itself,  of  what  it  is  that 
hath  the  power  to  do  them  much  good  or  harm,  are 
inclined  to  suppose,  and  feign  unto  themselves,  sev- 
eral kinds  of  powers  invisible;  and  to  stand  in  awe 
of  their  own  imaginations;  and  in  time  of  distress  to 
invoke  them;  as  also  in  the  time  of  an  expected  good 
success,  to  give  them  thanks ;  making  the  creatures  of 
their  own  fancy,  their  gods.  By  which  means  it  hath 
come  to  pass,  that  from  the  innumerable  variety  of 
fancy,  men  have  created  in  the  world  innumerable  sorts 
of  gods.  And  this  fear  of  things  invisible,  is  the 
natural  seed  of  that,  which  every  one  in  himself  calleth 
religion ;  and  in  them  that  worship,  or  fear  that  power 
otherwise  than  they  do,  superstition. 

And  this  seed  of  religion,  having  been  observed 
by  many;  some  of  those  that  have  observed  it,  have 
been  inclined  thereby  to  nourish,  dress,  and  form 
it  into  laws;  and  to  add  to  it  of  their  own  invention, 
any  opinion  of  the  causes  of  future  events,  by  which 
they  thought  they  should  be  best  able  to  govern 
others,  and  make  unto  themselves  the  greatest  use 
of  their  powers. 

CHAPTER  XII. 

OF  RELIGION. 

Seeing  there  are  no  signs,  nor  fruit  of  religion,  but 
in  man  only;  there  is  no  cause  to  doubt,  but  that 
the  seed  of  religion,  is  also  only  in  man ;  and  con- 


OF  RELIGION.  167 

sisteth  in  some  peculiar  quality,  or  at  least  in  some 
eminent  degree  thereof,  not  to  be  found  in  any  other 
living  creatures. 

And  first,  it  is  peculiar  to  the  nature  of  man,  to  be 
inquisitive  into  the  causes  of  the  events  they  see, 
some  more,  some  less ;  but  all  men  so  much,  as  to 
be  curious  in  the  search  of  the  causes  of  their  own 
good  and  evil  fortune. 

Secondly,  upon  the  sight  of  anything  that  hath  a 
beginning,  to  think  also  it  had  a  cause,  which  deter- 
mined the  same  to  begin,  then  when  it  did,  rather  than 
sooner  or  later. 

Thirdly,  whereas  there  is  no  other  felicity  of  beasts, 
but  the  enjoying  of  their  quotidian  food,  ease,  and 
lusts;  as  having  little  or  no  foresight  of  the  time  to 
come,  for  want  of  observation,  and  memory  of  the 
order,  consequence,  and  dependence  of  the  things  they 
see;  man  observeth  how  one  event  hath  been  produced 
by  another ;  and  remembereth  in  them  antecedence  and 
consequence;  and  when  he  cannot  assure  himself  of 
the  true  causes  of  things,  (for  the  causes  of  good  and 
evil  fortune  for  the  most  part  are  invisible,)  he  sup- 
poses causes  of  them,  either  such  as  his  own  fancy 
suggesteth ;  or  trusteth  the  authority  of  other  men, 
such  as  he  thinks  to  be  his  friends,  and  wiser  than 
himself. 

The  two  first,  make  anxiety.  For  being  assured 
that  there  be  causes  of  all  things  that  have  arrived 
hitherto,  or  shall  arrive  hereafter;  it  is  impossible 
for  a  man,  who  continually  endeavoureth  to  secure 
himself  against  the  evil  he  fears,  and  procure  the  good 
he  desireth,  not  to  be  in  a  perpetual  solicitude  of  the 
time  to  come ;  so  that  every  man,  especially  those  that 
are  over  provident,  are  in  a  state  like  to  that  of  Pro- 


168  LEVIATHAN. 

metheus.  For  as  Prometheus,  which  interpreted,  is 
the  prudent  man,  was  bound  to  the  hill  Caucasus,  a 
place  of  large  prospect,  where,  an  eagle  feeding  on  his 
liver,  devoured  in  the  day,  as  much  as  was  repaired 
in  the  night:  so  that  man,  which  looks  too  far  before 
him,  in  the  care  of  future  time,  hath  his  heart  all  the 
day  long,  gnawed  on  by  fear  of-  death,  poverty,  or 
other  calamity;  and  has  no  repose,  nor  pause  of  his 
anxiety  but  in  sleep. 

This  perpetual  fear,  always  accompanying  mankind 
in  the  ignorance  of  causes,  as  it  were  in  the  dark, 
must  needs  have  for  object  something.  And  therefore 
when  there  is  nothing  to  be  seen,  there  is  nothing  to 
accuse,  either  of  their  good,  or  evil  fortune,  but  some 
pozver,  or  agent  invisible:  in  which  sense  perhaps  it 
was,  that  some  of  the  old  poets  said,  that  the  gods 
were  at  first  created  by  human  fear:  which  spoken  of 
the  gods,  that  is  to  say,  of  the  many  gods  of  the 
Gentiles,  is  very  true.  But  the  acknowledging  of  one 
God,  eternal,  infinite,  and  omnipotent,  may  more  easily 
be  derived  from  the  desire  men  have  to  know  the 
causes  of  natural  bodies,  and  their  several  virtues,  and 
operations ;  than  from  the  fear  of  what  was  to  befall 
them  in  time  to  come.  For  he  that  from  any  effect 
he  seeth  come  to  pass,  should  reason  to  the  next  and 
immediate  cause  thereof,  and  from  thence  to  the  cause 
of  that  cause,  and  plunge  himself  profoundly  in  the 
pursuit  of  causes ;  shall  at  last  come  to  this,  that  there 
must  be,  as  even  the  heathen  philosophers  confessed, 
one  first  mover ;  that  is,  a  first,  and  an  eternal  cause  of 
all  things ;  which  is  that  which  men  mean  by  the  name 
of  God :  and  all  this  without  thought  of  their  fortune ; 
the  solicitude  whereof,  both  inclines  to  fear,  and  hin- 
ders  them  from  the   search   of  the  causes   of  other 


OF  RELIGION.  169 

things;  and  thereby  gives  occasion  of  feigning  of  as 
many  gods,  as  there  be  men  that  feign  them. 

And  for  the  matter,  or  substance  of  the  invisible 
agents,  so  fancied;  they  could  not  by  natural  cogita- 
tion, fall  upon  any  other  conceit,  but  that  it  was  the 
same  with  that  of  the  soul  of  man;  and  that  the  soul 
of  man,  was  of  the  same  substance,  with  that  which 
appeareth  in  a  dream,  to  one  that  sleepeth;  or  in  a 
looking-glass,  to  one  that  is  awake;  which,  men  not 
knowing  that  such  apparitions  are  nothing  else  but 
creatures  of  the  fancy,  think  to  be  real,  and  external 
substances;  and  therefore  call  them  ghosts;  as  the 
Latins  called  them  imagines,  and  umbra;  and  thought 
them  spirits,  that  is,  thin  aerial  bodies;  and  those  in- 
visible agents,  which  they  feared,  to  be  like  them ;  save 
that  they  appear,  and  vanish  when  they  please.  But 
the  opinion  that  such  spirits  were  incorporeal,  or  im- 
material, could  never  enter  into  the  mind  of  any  man 
by  nature;  because,  though  men  may  put  together 
words  of  contradictory  signification,  as  spirit,  and  in- 
corporeal; yet  they  can  never  have  the  imagination  of 
any  thing  answering  to  them :  and  therefore,  men  that 
by  their  own  meditation,  arrive  to  the  acknowledgment 
of  one  infinite,  omnipotent,  and  eternal  God,  chose 
rather  to  confess  he  is  incomprehensible,  and  above 
their  understanding,  than  to  define  his  nature  by  spirit 
incorporeal,  and  then  confess  their  definition  to  be 
unintelligible :  or  if  they  give  him  such  a  title,  it  is  not 
dogmatically,  with  intention  to  make  the  divine  nature 
understood ;  but  piously,  to  honour  him  with  attributes, 
of  significations,  as  remote  as  they  can  from  the  gross- 
ness  of  bodies  visible. 


PART  II. 

CHAPTER  XXXI. 

OF   THE    KINGDOM    OF   GOD   BY    NATURE. 


The  end  of  worship  amongst  men,  is  power.  For 
where  a  man  seeth  another  worshipped,  he  supposeth 
him  powerful,  and  is  the  readier  to  obey  him;  which 
makes  his  power  greater.  But  God  has  no  ends:  the 
worship  we  do  him,  proceeds  from  our  duty,  and  is 
directed  according  to  our  capacity,  by  those  rules  of 
honour,  that  reason  dictateth  to  be  done  by  the  weak 
to  the  more  potent  men,  in  hope  of  benefit,  for  fear 
of  damage,  or  in  thankfulness  for  good  already  re- 
ceived from  them. 

That  we  may  know  what  worship  of  God  is  taught 
us  by  the  light  of  nature,  I  will  begin  with  his  attri- 
butes. Where,  first,  it  is  manifest,  we  ought  to  attrib- 
ute to  him  existence.  For  no  man  can  have  the  will 
to  honour  that,  which  he  thinks  not  to  have  any  being. 

Secondly,  that  those  philosophers,  who  said  the 
world,  or  the  soul  of  the  world  was  God,  spake  un- 
worthily of  him;  and  denied  his  existence.  For  by 
God,  is  understood  the  cause  of  the  world;  and  to 
say  the  world  is  God,  is  to  say  there  is  no  cause  of 
it,  that  is,  no  God. 

Thirdly,  to  say  the  world  was  not  created,  but 
171 


i72  LEVIATHAN. 

eternal,  seeing  that  which  is  eternal  has  no  cause,  is 
to  deny  there  is  a  God. 

Fourthly,  that  they  who  attributing,  as  they  think, 
ease  to  God,  take  from  him  the  care  of  mankind; 
take  from  him  his  honour:  for  it  takes  away  men's 
love,  and  fear  of  him ;  which  is  the  root  of  honour. 

Fifthly,  in  those  things  that  signify  greatness,  and 
power ;  to  say  he  is  finite,  is  not  to  honour  him :  for  it 
is  not  a  sign  of  the  will  to  honour  God,  to  attribute 
to  him  less  than  we  can;  and  finite,  is  less  than  we 
can ;  because  to  finite,  it  is  easy  to  add  more. 

Therefore  to  attribute  figure  to  him,  is  not  honour ; 
for  all  figure  is  finite : 

Nor  to  say  we  conceive,  and  imagine,  or  have  an 
idea  of  him,  in  our  mind :  for  whatsoever  we  conceive 
is  finite: 

Nor  to  attribute  to  him  parts,  or  totality;  which  are 
the  attributes  only  of  things  finite : 

Nor  to  say  he  is  in  this,  or  that  place:  for  whatso- 
ever is  in  place,  is  bounded,  and  finite: 

Nor  that  he  is  moved,  or  resteth:  for  both  these  at- 
tributes ascribe  to  him  place: 

Nor  that  there  be  more  Gods  than  one;  because  it 
implies  them  all  finite :  for  there  cannot  be  more  than 
one  infinite: 

Nor  to  ascribe  to  him,  (unless  metaphorically,  mean- 
ing not  the  passion  but  the  effect,)  passions  that  par- 
take of  grief;  as  repentance,  anger,  mercy:  or  of  want; 
as  appetite,  hope,  desire;  or  of  any  passive  faculty: 
for  passion,  is  power  limited  by  somewhat  else. 

And  therefore  when  we  ascribe  to  God  a  will,  it  is 
not  to  be  understood,  as  that  of  man,  for  a  rational 
appetite;  but  as  the  power,  by  which  he  effecteth 
every  thing. 


THE  KINGDOM  OF  GOD  BY  NATURE.  173 

Likewise  when  we  attribute  to  him  sight,  and  other 
acts  of  sense;  as  also  knowledge,  and  understanding; 
which  in  us  is  nothing  else,  but  a  tumult  of  the  mind, 
raised  by  external  things  that  press  the  organical  parts 
of  man's  body :  for  there  is  no  such  thing  in  God ; 
and  being  things  that  depend  on  natural  causes,  cannot 
be  attributed  to  him. 

He  that  will  attribute  to  God,  nothing  but  what  is 
warranted  by  natural  reason,  must  either  use  such 
negative  attributes,  as  infinite,  eternal,  incomprehen- 
sible; or  superlatives,  as  most  high,  most  great,  and  the 
like;  or  indefinite,  as  good,  just,  holy,  creator;  and  in 
such  sense  as  if  he  meant  not  to  declare  what  he  is, 
(for  that  were  to  circumscribe  him  within  the  limits  of 
our  fancy,)  but  how  much  we  admire  him,  and  how 
ready  we  would  be  to  obey  him ;  which  is  a  sign 
of  humility,  and  of  a  will  to  honour  him  as  much  as 
we  can.  For  there  is  but  one  name  to  signify  our 
conception  of  his  nature,  and  that  is,  I  am  :  and  but 
one  name  of  his  relation  to  us,  and  that  is,  God;  in 
which  is  contained  Father,  King,  and  Lord. 


CHAPTER  XXXIV. 

OF  THE  SIGNIFICATION  OF  SPIRIT,  ANGEL,  AND  INSPIRA- 
TION  IN   THE  BOOKS  OF   HOLY  SCRIPTURE. 

Seeing  the  foundation  of  all  true  ratiocination,  is 
the  constant  signification  of  words ;  which  in  the  doc- 
trine following,  dependeth  not,  as  in  natural  science, 
on  the  will  of  the  writer,  nor,  as  in  common  conversa- 
tion, on  vulgar  use,  but  on  the  sense  they  carry  in  the 


174  LEVIATHAN. 

Scripture ;  it  is  necessary,  before  I  proceed  any  further, 
to  determine,  out  of  the  Bible,  the  meaning  of  such 
words,  as  by  their  ambiguity,  may  render  what  I  am 
to  infer  upon  them,  obscure,  or  disputable.  I  will 
begin  with  the  words  body  and  spirit,  which  in  the 
language  of  the  Schools  are  termed,  substances,  cor- 
poreal, and  incorporeal. 

The  word  body,  in  the  most  general  acceptation, 
signifieth  that  which  filleth,  or  occupieth  some  certain 
room,  or  imagined  place;  and  dependeth  not  on  the 
imagination,  but  is  a  real  part  of  that  we  call  the 
universe.  For  the  universe,  being  the  aggregate  of  all 
bodies,  there  is  no  real  part  thereof  that  is  not  also 
body;  nor  any  thing  properly  a  body,  that  is  not  also 
part  of  that  aggregate  of  all  bodies,  the  universe. 
The  same  also,  because  bodies  are  subject  to  change, 
that  is  to  say,  to  variety  of  apparence  to  the  sense  of 
living  creatures,  is  called  substance,  that  is  to  say, 
subject  to  various  accidents :  as  sometimes  to  be 
moved;  sometimes  to  stand  still;  and  to  seem  to  our 
senses  sometimes  hot,  sometimes  cold,  sometimes  of 
one  colour,  smell,  taste,  or  sound,  sometimes  of  an- 
other. And  this  diversity  of  seeming,  produced  by 
the  diversity  of  the  operation  of  bodies  on  the  organs 
of  our  sense,  we  attribute  to  alterations  of  the  bodies 
that  operate,  and  call  them  accidents  of  those  bodies. 
And  according  to  this  acceptation  of  the  word,  sub- 
stance and  body  signify  the  same  thing;  and  therefore 
substance  incorporeal  are  words,  which  when  they  are 
joined  together,  destroy  one  another,  as  if  a  man 
should  say,  an  incorporeal  body. 

But  in  the  sense  of  common  people,  not  all  the  uni- 
verse is  called  body,  but  only  such  parts  thereof  as 
they  can  discern  by  the  sense  of  feeling,  to  resist  their 


SPIRIT,  ANGEL,  AND  INSPIRATION.  175 

force,  or  by  the  sense  of  their  eyes,  to  hinder  them 
from  a  farther  prospect.  Therefore  in  the  common 
language  of  men,  air,  and  aerial  substances,  use  not  to 
be  taken  for  bodies,  but  (as  often  as  men  are  sensible 
of  their  effects)  are  called  wind,  or  breath,  or  (because 
the  same  are  called  in  the  Latin  spiritus)  spirits;  as 
when  they  call  that  aerial  substance,  which  in  the  body 
of  any  living  creature  gives  it  life  and  motion,  vital 
and  animal  spirits.  But  for  those  idols  of  the  brain, 
which  represent  bodies  to  us,  where  they  are  not,  as  in 
a  looking-glass,  in  a  dream,  or  to  a  distempered  brain 
waking,  they  are,  as  the  apostle  saith  generally  of  all 
idols,  nothing;  nothing  at  all,  I  say,  there  where  they 
seem  to  be ;  and  in  the  brain  itself,  nothing  but  tumult, 
proceeding  either  from  the  action  of  the  objects,  or 
from  the  disorderly  agitation  of  the  organs  of  our 
sense.  And  men,  that  are  otherwise  employed,  than 
to  search  into  their  causes,  know  not  of  themselves, 
what  to  call  them;  and  may  therefore  easily  be  per- 
suaded, by  those  whose  knowledge  they  much  rev- 
erence, some  to  call  them  bodies,  and  think  them  made 
of  air  compacted  by  a  power  supernatural,  because  the 
sight  judges  them  corporeal ;  and  some  to  call  them 
/pints,  because  the  sense  of  touch  discerneth  nothing 
in  the  place  where  they  appear,  to  resist  their  fingers : 
so  that  the  proper  signification  of  spirit  in  common 
speech,  is  either  a  subtle,  fluid,  and  invisible  body,  or  a 
ghost,  or  other  idol  or  phantasm  of  the  imagination. 
But  for  metaphorical  significations,  there  be  many: 
for  sometimes  it  is  taken  for  disposition  or  inclination 
of  the  mind ;  as  when  for  the  disposition  to  controul 
the  sayings  of  other  men,  we  say,  a  spirit  of  contra- 
diction; for  a  disposition  to  nncleanness,  an  unclean 
spirit;  for  perverseness,  a  froward  spirit;  for  sullen- 


i;6  LEVIATHAN. 

ncss,  a  dumb  spirit;  and  for  inclination  to  godliness 
and  God's  service,  the  Spirit  of  God:  sometimes  for 
any  eminent  ability  or  extraordinary  passion,  or  dis- 
ease of  the  mind,  as  when  great  wisdom  is  called  the 
spirit  of  wisdom;  and  madmen  are  said  to  be  possessed 
with  a  spirit. 

Other  signification  of  spirit  I  find  nowhere  any ;  and 
where  none  of  these  can  satisfy  the  sense  of  that  word 
in  Scripture,  the  place  falleth  not  under  human  under- 
standing; and  our  faith  therein  consisteth  not  in  our 
opinion ;  but  in  our  submission ;  as  in  all  places  where 
God  is  said  to  be  a  Spirit;  or  whereby  the  Spirit  of 
God,  is  meant  God  himself.  For  the  nature  of  God 
is  incomprehensible ;  that  is  to  say,  we  understand 
nothing  of  zvhat  he  is,  but  only  that  he  is;  and  there- 
fore the  attributes  we  give  him,  are  not  to  tell  one 
another,  what  he  is,  nor  to  signify  our  opinion  of  his 
nature,  but  our  desire  to  honour  him  with  such  names 
as  we  conceive  most  honourable  amongst  ourselves. 

Gen.  i.  2.  The  Spirit  of  God  moved  upon  the  face 
of  the  waters.  Here  if  by  the  Spirit  of  God  be  meant 
God  himself,  then  is  motion  attributed  to  God,  and 
consequently  place,  which  are  intelligible  only  of 
bodies,  and  not  of  substances  incorporeal ;  and  so  the 
place  is  above  our  understanding,  that  can  conceive 
nothing  moved  that  changes  not  place,  or  that  has  not 
dimension ;  and  whatsoever  has  dimension,  is  body. 
But  the  meaning  of  those  words  is  best  understood  by 
the  like  place,  {Gen.  viii.  1.)  where  when  the  earth  was 
covered  with  waters,  as  in  the  beginning,  God  intend- 
ing to  abate  them,  and  again  to  discover  the  dry  land, 
useth  the  like  words,  7"  will  bring  my  Spirit  upon  the 
earth,  and  the  waters  shall  be  diminished:  in  which 
place,  by  Spirit  is  understood  a  wind,  that  is  an  air  or 


SPIRIT,  ANGEL,  AND  INSPIRATION.  177 

spirit  moved,  which  might  be  called,  as  in  the  former 
place,  the  Spirit  of  God,  because  it  was  God's  work. 


Concerning  the  creation  of  angels,  there  is  nothing 
delivered  in  the  Scriptures.  That  they  are  spirits, 
is  often  repeated:  but  by  the  name  of  spirit,  is  signi- 
fied both  in  Scripture,  and  vulgarly,  both  amongst 
Jews  and  Gentiles,  sometimes  thin  bodies:  as  the  air, 
the  wind,  the  spirits  vital  and  animal  of  living  crea- 
tures ;  and  sometimes  the  images  that  rise  in  the  fancy 
in  dreams  and  visions;  which  are  not  real  substances, 
nor  last  any  longer  than  the  dream,  or  vision  they 
appear  in;  which  apparitions,  though  no  real  sub- 
stances, but  accidents  of  the  brain;  yet  when  God 
raiseth  them  supernaturally,  to  signify  his  will,  they 
are  not  improperly  termed  God's  messengers,  that  is 
to  say,  his  angels. 

And  as  the  Gentiles  did  vulgarly  conceive  the  im- 
agery of  the  brain,  for  things  really  subsistent  without 
them,  and  not  dependent  on  the  fancy ;  and  out  of  them 
framed  their  opinions  of  demons,  good  and  evil ;  which 
because  they  seemed  to  subsist  really,  they  called  sub- 
stances; and,  because  they  could  not  feel  them  with 
their  hands,  incorporeal:  so  also  the  Jews,  upon  the 
same  ground,  without  any  thing  in  the  Old  Testament 
that  constrained  them  thereunto,  had  generally  an 
opinion,  except  the  sect  of  the  Sadducees,  that  those 
apparitions,  which  it  pleased  God  sometimes  to  pro- 
duce in  the  fancy  of  men,  for  his  own  service,  and 
therefore  called  them  his  angels,  were  substances,  not 
dependent  on  the  fancy,  but  permanent  creatures  of 
God ;  whereof  those  which  they  thought  were  good  to 
them,  they  esteemed  the  angels  of  God,  and  those  they 


178  LEVIATHAN. 

thought  would  hurt  them,  they  called  evil  angels,  or 
evil  spirits ;  such  as  was  the  spirit  of  Python,  and  the 
spirits  of  madmen,  of  lunatics  and  epileptics :  for  they 
esteemed  such  as  were  troubled  with  such  diseases, 
demoniacs. 

But  if  we  consider  the  places  of  the  Old  Testament 
where  angels  are  mentioned,  we  shall  find,  that  in 
most  of  them,  there  can  nothing  else  be  understood 
by  the  word  angel,  but  some  image  raised,  super- 
naturally,  in  the  fancy,  to  signify  the  presence  of  God 
in  the  execution  of  some  supernatural  work ;  and  there- 
fore in  the  rest,  where  their  nature  is  not  expressed, 
it  may  be  understood  in  the  same  manner. 


To  mention  all  the  places  of  the  Old  Testament 
where  the  name  of  angel  is  found,  would  be  too  long. 
Therefore  to  comprehend  them  all  at  once,  I  say,  there 
is  no  text  in  that  part  of  the  Old  Testament,  which 
the  Church  of  England  holdeth  for  canonical,  from 
which  we  can  conclude,  there  is,  or  hath  been  created, 
any  permanent  thing,  understood  by  the  name  of  spirit 
or  angel,  that  hath  not  quantity ;  and  that  may  not  be 
by  the  understanding  divided;  that  is  to  say,  con- 
sidered by  parts ;  so  as  one  part  may  be  in  one  place, 
and  the  next  part  in  the  next  place  to  it ;  and,  in  sum, 
which  is  not  (taking  body  for  that,  which  is  somewhat 
or  some  where,)  corporeal;  but  in  every  place,  the 
sense  will  bear  the  interpretation  of  angel,  for  messen- 
ger; as  John  Baptist  is  called  an  angel,  and  Christ 
the  Angel  of  the  Covenant;  and  as,  according  to  the 
same  analogy,  the  dove  and  the  fiery  tongues,  in  that 
they  were  signs  of  God's  special  presence,  might  also 
be  called  angels.     Though  we  find  in  Daniel  two  names 


SPIRIT,  ANGEL,  AND  INSPIRATION.  179 

of  angels,  Gabriel  and  Michael;  yet  it  is  clear  out  of 
the  text  itself,  (Dan.  xii.  1)  that  by  Michael  is  meant 
Christ,  not  as  an  angel,  but  as  a  prince:  and  that 
Gabriel,  as  the  like  apparitions  made  to  other  holy  men 
in  their  sleep,  was  nothing  but  a  supernatural  phan- 
tasm, by  which  it  seemed  to  Daniel,  in  his  dream,  that 
two  saints  being  in  talk,  one  of  them  said  to  the  other, 
Gabriel,  Let  us  make  this  man  understand  his  vision: 
for  God  needeth  not  to  distinguish  his  celestial  servants 
by  names,  which  are  useful  only  to  the  short  memories 
of  mortals.  Nor  in  the  New  Testament  is  there  any 
place,  out  of  which  it  can  be  proved,  that  angels,  except 
when  they  are  put  for  such  men  as  God  hath  made 
the  messengers  and  ministers  of  his  word  or  works, 
are  things  permanent,  and  withal  incorporeal.  That 
they  are  permanent,  may  be  gathered  from  the  words 
of  our  Saviour  himself,  (Matt.  xxv.  41)  where  he 
saith,  it  shall  be  said  to  the  wicked  in  the  last  day, 
Go  ye  cursed  into  everlasting  fire  prepared  for  the 
Devil  and  his  angels:  which  place  is  manifest  for  the 
permanence  of  evil  angels,  (unless  we  might  think  the 
name  of  Devil  and  his  angels  may  be  understood  of 
the  Church's  adversaries  and  their  ministers)  ;  but  then 
it  is  repugnant  to  their  immateriality;  because  ever- 
lasting fire  is  no  punishment  to  impatible  substances, 
such  as  are  all  things  incorporeal.  Angels  therefore 
are  not  thence  proved  to  be  incorporeal.  In  like  man- 
ner where  St.  Paul  says,  (1  Cor.  vi.  3)  Know  ye  not 
that  we  shall  judge  the  angels?  and  2  Pet.  ii.  4,  For 
if  God  spared  not  the  angels  that  sinned,  but  cast  them 
down  into  hell:  and  (hide  i.  6)  And  the  angels  that 
kept  not  their  first  estate,  but  left  their  own  habitation, 
he  hath  reserved  in  everlasting  chains  under  darkness 
unto  the  judgment  of  the  last  day:  though  it  prove  the 


i8o  LEVIATHAN. 

permanence  of  angelical  nature,  it  confirmeth  also  their 
materiality.  And  (Matt.  xxii.  30)  In  the  resurrection 
men  do  neither  marry  nor  give  in  marriage,  but  are  as 
the  angels  of  God  in  heaven:  but  in  the  resurrection 
men  shall  be  permanent,  and  not  incorporeal ;  so  there- 
fore also  are  the  angels. 

There  be  divers  other  places  out  of  which  may  be 
drawn  the  like  conclusion.  To  men  that  understand 
the  signification  of  these  words,  substance,  and  incor- 
poreal; as  incorporeal  is  taken,  not  for  subtle  body, 
but  for  not  body;  they  imply  a  contradiction :  insomuch 
as  to  say,  an  angel  or  spirit  is  in  that  sense  an  incor- 
poreal substance,  is  to  say  in  effect,  there  is  no  angel 
nor  spirit  at  all.  Considering  therefore  the  signifi- 
cation of  the  word  angel  in  the  Old  Testament,  and 
the  nature  of  dreams  and  visions  that  happen  to  men 
by  the  ordinary  way  of  nature ;  I  was  inclined  to  this 
opinion,  that  angels  were  nothing  but  supernatural 
apparitions  of  the  fancy,  raised  by  the  special  and 
extraordinary  operation  of  God,  thereby  to  make  his 
presence  and  commandments  known  to  mankind,  and 
chiefly  to  his  own  people.  But  the  many  places  of 
the  New  Testament,  and  our  Saviour's  own  words,  and 
in  such  texts,  wherein  is  no  suspicion  of  corruption 
of  the  Scripture,  have  extorted  from  my  feeble  reason, 
an  acknowledgment  and  belief,  that  there  be  also  angels 
substantial,  and  permanent.  But  to  believe  they  be 
in  no  place,  that  is  to  say,  no  where,  that  is  to  say, 
nothing,  as  they,  though  indirectly,  say,  that  will  have 
them  incorporeal,  cannot  by  Scripture  be  evinced. 


SELECTED  PASSAGES 

FROM 

ELEMENTORUM  PHILOSOPHIC  SECTIO 
PRIMA  DE  CORPORE. 


SELECTIONS  FROM  DE  CORPORE. 

The  Elements  of  Philosophy  Concerning  Body  is  an 
English  version,  by  an  unnamed  translator,  of  the  De  Corpore 
of  Hobbes.  Though  the  translation  was  revised  by  Hobbes, 
it  is  none  the  less  an  unsatisfactory  version  —  sometimes 
inexact,  again  so  literal  that  it  is  fairly  uncouth,  and 
at  times  even  positively  misleading.  The  following  selections, 
topically  ordered,  comprise  definitions  and  statements  of  fun- 
damental importance  to  the  system  of  Hobbes.  It  will  appear 
that  the  Latin  is  both  clearer  and  more  forcible  than  the  cor- 
responding English ;  yet  the  English  rendering  of  these  pas- 
sage* will  be  found  to  be  "  for  substance  of  doctrine  "  correct. 


182 


I.     IMAGINARY  SPACE  AND  TIME. 
Chapter  VII.  (i),  (2)  and  (3),  in  part. 

1.  Doctrinae  naturalis  exordium,  optime  (ut  supra 
ostensum  est)  a  privatione,  id  est,  a  ficta  universi  sub- 
latione,  capiemus.  Supposita  autem  tali  rerum  annihi- 
latione,  quaeret  fortasse  aliquis,  quid  reliquum  esset, 
de  quo  homo  aliquis  (quern  ab  hoc  universo  rerum  in- 
teritu  unicum  excipimus)  philosophari,  vel  omnino 
ratiocinari,  vel  cui  rei  nomen  aliquod  ratiocinandi  causa 
imponere  posset. 

Dico  igitur,  remansuras  illi  homini,  mundi  et  cor- 
porum  omnium,  quae,  ante  sublationem  eorum,  oculis 
aspexerat,  vel  aliis  sensibus  perceperat,  ideas,  id  est 
memoriam  imaginationemque  magnitudinum,  motuum, 
sonorum,  colorum,  &c.  atque  etiam  eorum  ordinis  et 
partium;  quae  omnia  etsi  ideae  tantum  et  phantasmata 
sint,  ipsi  imaginanti  interne  accidentia,  nihilominus  tan- 
quam  externa,  et  a  virtute  animi  minime  dependentia, 
apparitura  esse.     .     .     . 

2.  Jam  si  meminerimus,  seu  phantasma  habuerimus 
alicujus  rei,  quae  extiterat  ante  suppositam  rerum  ex- 
ternarum  sublationem,  nee  considerare  velimus,  qualis 
ea  res  erat,*  sed  simpliciter  quod  erat  extra  animum, 
habemus  id,  quod  appellamus  spatium,  imaginarium 
quidem,  quia  merum  phantasma,  sed  tamen  illud  ipsum, 
quod  ab  omnibus  sic  appellatur.  .  .  .  Reversus 
itaque  ad  institutum,  spatii  definitionem  hanc  esse  dico, 


Cf.  the  English  version. 

183 


i?4  DE   CORP  ORE. 

spatium  est  phantasma  rei  existentis,  quatenus  exis- 
tentis* id  est,  nullo  alio  ejus  rei  accidente  considerato 
praeterquam  quod  apparet  extra  imaginantem. 

3.  .  .  .  Tota  ergo  definitio  temporis  talis  est, 
tempus  est  phantasma  motus,  quatenus  in  motu  imagi- 
namur  prius  et  posterius,  sive  successionem  ;*  quae  con- 
venit  cum  definitione  Aristotelica,  tempus  est  Humerus 
motus  secundum  prius  et  posterius  et  tempus  est  phan- 
tasma motus  numerati,  illud  autem  tempus  est  mensura 
motus  non  ita  recte  dicitur,  nam  tempus  per  motum, 
non  autem  motum  per  tempus,  mensuramus. 

II.    BODY  AND  ACCIDENT. 

a.  Definitions. 

Chapter  VIII.  (1)  and  (2),  in  part. 

1.  Intellecto  jam  quid  sit  spatium  imaginarium,  in 
quo  nihil  esse  externum  supposuimus,  sed  meram 
eorum,  quae  olim  existentia  imagines  suas  in  animo  re- 
liquerant,  privationem ;  supponamus  deinceps  aliquid 
eorum  rursus  reponi,  sive  creari  denuo;  necesse  ergo 
est  ut  creatum  illud  sive  repositum,  non  modo 
occupet  aliquam  dicti  spatii  partem,  sive  cum  ea  coin- 
cidat  et  coextendatur,  sed  etiam  esse  aliquid,  quod  ab 
imaginationef  nostra  non  dependet.  Hoc  autem  ipsum 
est  quod  appellari  solet,  propter  extensionem  quidem, 
corpus;  propter  independentiam  autem  a  nostra  cogita- 
tionet  subsist  ens  per  se;  et  propterea  quod  extra  nos 


*  Cf.  the  English. 

t  Cf.  the  English,  and  note  both  how  loosely  it  conforms  to  the 
Latin  and  how  it  fails  to  distinguish  these  similar  but  differentiated 
terms. 


BODY  AND  ACCIDENT.  185 

subsistit,  existens;  denique  quia  sub  spatio  imaginario 
substerni  et  supponi  videtur*  ut  non  sensibus  sed  ra- 
tione  tantum  aliquid  ibi  esse  intelligatur,  supposition  et 
subjectiim.  Itaque  definitio  corporis  hujusmodi  est, 
corpus  est  quicquid  non  dependens  a  nostra  cogitationc 
cum  spatii  parte  aliqua  coincidit  vel  coextenditur. 

2.  Quid  autem  sit  accidens  non  tarn  facile  defini- 
tione  quam  exemplis  explicari  potest.  .  .  .  His 
ut  satisfiat,  optime,  .  .  .  respondent  illi  qui  acci- 
dens definiunt  esse  modum  corporis,  juxta  quenrf  con- 
cipitur;  quod  est  idem  ac  si  dicerent,  accidens  esse 
facultatem  corporis  qua  sui  conceptual  nobis  im- 
primit. 

b.  Body  as  occupying  real  space. 

Chapter  VIII.     (4). 

4.  Extensio  corporis  idem  est  quod  magnitudo  ejus, 
sive  id  quod  aliqui  vocant  spatium  reale ;  magnitudo 
autem  ilia  non  dependet  a  cogitatione  nostra,  sicut 
spatium  imaginarium,  hoc  enim  illius  efTectus  est,  mag- 
nitudo causa;  hoc  animi,  ilia  corporis  extra  animum 
existentis  accidens  est. 

III.     MOTION, 
a.  Definitions. 

Chapter  XV.  (1),  first  sentence. 

Proxima  ordine  tractatio  est  de  motu  et  magnitudine, 
corporum  accidentibus  maxime  communibus. 


*Cf.   the   English, 
t  Cf.  the  English. 


186  DE    CORPORE. 

Chapter  VIII.  (10),  in  part. 

Motus  est  continua  unins  loci  relictio  et  alterius  ac~ 
quisitio ;  locus  autem,  qui  relinquitur,  terminus  a  quo, 
qui  acquiritur,  terminus  ad  quern  dici  solet;  continuam 
dico,  propterea  quod  corpus  quantulumcumque  sit,  non 
potest  totum  simul  a  toto  loco  priore  ita  excedere,  ut 
pars  ejus  non  sit  in  parte  quae  sit  utrique  loco,  nimirum 
relicto  et  acquisito,  communis.     .     .     . 

Moveri  autem  aliquid  nisi  in  tempore  concipi  non 
potest.  Est  enim  tempus,  ex  definitione,  phantasma, 
id  est,  conceptus  motus ;  itaque  concipere  moveri  aliquid 
non  in  tempore  esset  concipere  motum  non  concepto 
motu,  quod  est  impossible. 

b.  Cause  of  Motion. 

Chapter  IX.    (7)   in  part. 

Causa  motus,  nulla  esse  potest  in  corpore  nisi  con- 
tiguo  et  moto.  Sint  enim  duo  corpora  quselibet  non 
contigua,  inter  quae  aut  spatium,  quod  inter jacet,  vacu- 
um sit,  aut  si  plenum,  plenum  tamen  corpore  quies- 
cente,  propositorum  autem  corporum  unum  quiescere 
supponatur.  Dico  quieturum  semper;  nam  si  move- 
bitur;  causa  ejus  motus  per  caput  8,  articulum  19,  erit 
in  corpore*  externo ;  si  igitur,  inter  ipsum  et  externum 
fllud,  vacuum  spatium  sit,  possumus  concipere,  utcun- 
que  se  habeant  corpora  externa  vel  ipsum  patiens 
(modo  supponatur  nunc  quiescere),  quieturum  esse 
quamdiu  ab  iis*  non  contingitur;  cum  autem  causa 
(per   definitionem)    sit   aggregatum   accidentium   om- 


*  Cf.  the  English. 


MOTION.  187 

nium  quibus  suppositis  effectum  non  sequi  concipi  non 
potest,  accidentia  qua?  sunt  vel  in  externis  vel  in  ipso 
patiente,  causa  futuri  motus  non  erit,  similiter  quia  con- 
cipi potest  id  quod  jam  quiescit  quieturum  adhuc,  eti- 
amsi  ab  alio  corpore  contingatur  modo  corpus  illud  non 
moveatur,  non  erit  causa  motus  in  contiguo  corpore 
quiescente.  Itaque  causa  motus  in  corpore  nulla  est, 
nisi  in  contiguo  et  moto. 

c.  All  Change  is  Motion. 

Chapter  IX.    (9). 

Hoc  posito,  necesse  est  ut  mutatio  aliud  non  sit  prae- 
ter  partium  corporis  mutati  motum.  Primo  enim  mu- 
tari  nihil  dicimus  praeterquam  quod  sensibus  nostris 
aliter  apparet  quam  ante  apparuit.  Secundo,  illae  ap- 
parentiae  sunt  ambse  effectus  producti  in  sentiente; 
itaque  si  diversi  sunt,  necesse  est  per  praecedentem,  ut 
vel  agentis  pars  aliqua  ante  quiescens  jam  moveatur,  et 
sic  mutatio  consistit  in  eo  motu ;  vel  ante  mota,  nunc 
aliter  moveatur,  et  sic  quoque  consistit  mutatio  in  novo 
motu,  vel  ante  mota  nunc  quiescat,  quod  fieri  nisi  per 
motum  non  posse  supra  demonstravimus,  et  ita  rursus 
mutatio  motus  est,  vel  denique  aliquid  horum  contingit 
patienti  vel  parti  ejus,  atque  ita  omni  modo  mutatio 
consistet  in  motu  partium  ejus  corporis  quod  sentitur, 
vel  ipsius  sentientis,  vel  utriusque.  Itaque  mutatio 
motus  est  (nimirum  partium  agentis  vel  patientis) 
quod  erat  propositum  demonstrare.  Huic  autem  con- 
sequens  est,  quietem  nullius  rei  causam  esse,  neque 
omnino  per  earn  quicquam  agi,  ut  quae  neque  motus 
neque  mutationis  ullius  causa  sit. 


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